opcodes/aarch64: rename fields[]

To be a fair global name space citizen, give it an aarch64_ prefix. In
two cases, drop a variable that's used only once.
diff --git a/opcodes/aarch64-asm.c b/opcodes/aarch64-asm.c
index a9d0aeb..75216fd 100644
--- a/opcodes/aarch64-asm.c
+++ b/opcodes/aarch64-asm.c
@@ -40,7 +40,6 @@
 insert_fields (aarch64_insn *code, aarch64_insn value, aarch64_insn mask, ...)
 {
   uint32_t num;
-  const aarch64_field *field;
   enum aarch64_field_kind kind;
   va_list va;
 
@@ -50,9 +49,8 @@
   while (num--)
     {
       kind = va_arg (va, enum aarch64_field_kind);
-      field = &fields[kind];
       insert_field (kind, code, value, mask);
-      value >>= field->width;
+      value >>= aarch64_fields[kind].width;
     }
   va_end (va);
 }
@@ -72,7 +70,7 @@
       {
 	kind = self->fields[i];
 	insert_field (kind, code, value, 0);
-	value >>= fields[kind].width;
+	value >>= aarch64_fields[kind].width;
       }
 }
 
diff --git a/opcodes/aarch64-dis.c b/opcodes/aarch64-dis.c
index 179addc..af62bd8 100644
--- a/opcodes/aarch64-dis.c
+++ b/opcodes/aarch64-dis.c
@@ -149,7 +149,6 @@
 extract_fields (aarch64_insn code, aarch64_insn mask, ...)
 {
   uint32_t num;
-  const aarch64_field *field;
   enum aarch64_field_kind kind;
   va_list va;
 
@@ -160,8 +159,7 @@
   while (num--)
     {
       kind = va_arg (va, enum aarch64_field_kind);
-      field = &fields[kind];
-      value <<= field->width;
+      value <<= aarch64_fields[kind].width;
       value |= extract_field (kind, code, mask);
     }
   va_end (va);
@@ -184,7 +182,7 @@
        i < ARRAY_SIZE (self->fields) && self->fields[i] != FLD_NIL; ++i)
     {
       kind = self->fields[i];
-      value <<= fields[kind].width;
+      value <<= aarch64_fields[kind].width;
       value |= extract_field (kind, code, 0);
     }
   return value;
@@ -1240,7 +1238,8 @@
   info->addr.base_regno = extract_field (FLD_Rn, code, 0);
   /* simm (imm9 or imm7)  */
   imm = extract_field (self->fields[0], code, 0);
-  info->addr.offset.imm = sign_extend (imm, fields[self->fields[0]].width - 1);
+  info->addr.offset.imm
+    = sign_extend (imm, aarch64_fields[self->fields[0]].width - 1);
   if (self->fields[0] == FLD_imm7
       || info->qualifier == AARCH64_OPND_QLF_imm_tag)
     /* scaled immediate in ld/st pair instructions.  */
diff --git a/opcodes/aarch64-opc.c b/opcodes/aarch64-opc.c
index f7dae4b..5980841 100644
--- a/opcodes/aarch64-opc.c
+++ b/opcodes/aarch64-opc.c
@@ -223,7 +223,7 @@
 
 /* Instruction bit-fields.
 +   Keep synced with 'enum aarch64_field_kind'.  */
-const aarch64_field fields[] =
+const aarch64_field aarch64_fields[] =
 {
     {  0,  0 },	/* NIL.  */
     {  8,  4 },	/* CRm: in the system instructions.  */
diff --git a/opcodes/aarch64-opc.h b/opcodes/aarch64-opc.h
index d46c56d..68e297f 100644
--- a/opcodes/aarch64-opc.h
+++ b/opcodes/aarch64-opc.h
@@ -251,7 +251,7 @@
 
 typedef struct aarch64_field aarch64_field;
 
-extern const aarch64_field fields[];
+extern const aarch64_field aarch64_fields[];
 
 /* Operand description.  */
 
@@ -427,7 +427,7 @@
 get_operand_field_width (const aarch64_operand *operand, unsigned n)
 {
   assert (operand->fields[n] != FLD_NIL);
-  return fields[operand->fields[n]].width;
+  return aarch64_fields[operand->fields[n]].width;
 }
 
 /* Return the total width of the operand *OPERAND.  */
@@ -437,7 +437,7 @@
   int i = 0;
   unsigned width = 0;
   while (operand->fields[i] != FLD_NIL)
-    width += fields[operand->fields[i++]].width;
+    width += aarch64_fields[operand->fields[i++]].width;
   assert (width > 0 && width < 32);
   return width;
 }
@@ -482,7 +482,7 @@
 static inline int
 gen_sub_field (enum aarch64_field_kind kind, int lsb_rel, int width, aarch64_field *ret)
 {
-  const aarch64_field *field = &fields[kind];
+  const aarch64_field *field = &aarch64_fields[kind];
   if (lsb_rel < 0 || width <= 0 || lsb_rel + width > field->width)
     return 0;
   ret->lsb = field->lsb + lsb_rel;
@@ -528,7 +528,7 @@
 insert_field (enum aarch64_field_kind kind, aarch64_insn *code,
 	      aarch64_insn value, aarch64_insn mask)
 {
-  insert_field_2 (&fields[kind], code, value, mask);
+  insert_field_2 (&aarch64_fields[kind], code, value, mask);
 }
 
 /* Extract field KIND of CODE and return the value.  MASK can be zero or the
@@ -538,7 +538,7 @@
 extract_field (enum aarch64_field_kind kind, aarch64_insn code,
 	       aarch64_insn mask)
 {
-  return extract_field_2 (&fields[kind], code, mask);
+  return extract_field_2 (&aarch64_fields[kind], code, mask);
 }
 
 extern aarch64_insn