RISC-V: PR28291, Fix the gdb fails that PR27916 caused.

* According to PR28291, we get the following unexpected gdb behavior,

(gdb) disassemble 0x0,+4
Dump of assembler code from 0x0 to 0x4:
   0x0000000000000000:
   0x0000000000000001:
   0x0000000000000002:
   0x0000000000000003:
End of assembler dump.

* This patch should fix it to the right behavior,

(gdb) disassemble 0x0,+4
Dump of assembler code from 0x0 to 0x4:
   0x0000000000000000:  Cannot access memory at address 0x0

opcodes/
    pr 28291
    * riscv-dis.c (print_insn_riscv): Return STATUS if it is not zero.

opcodes/riscv-dis.c

diff --git a/opcodes/riscv-dis.c b/opcodes/riscv-dis.c
index 30b42ef..171aea2 100644
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -793,7 +793,7 @@
       if (status != 0)
 	{
 	  (*info->memory_error_func) (status, memaddr, info);
-	  return 1;
+	  return status;
 	}
       insn = (insn_t) bfd_getl16 (packet);
       dump_size = riscv_insn_length (insn);
@@ -805,7 +805,7 @@
   if (status != 0)
     {
       (*info->memory_error_func) (status, memaddr, info);
-      return 1;
+      return status;
     }
   insn = (insn_t) bfd_get_bits (packet, dump_size * 8, false);