bfd/TIC4x: correct COFF swapping functions for mixed-endianness binaries

Commit 3fa785190a4f ("Altered the CREATE_xxx_COFF_TARGET_VEC macro
arguments") pretty clearly screwed up the data swapping functions in the
new CREATE_BIGHDR_COFF_TARGET_VEC() macro. Since the flaw went unnoticed,
and since the correction doesn't cause any testsuite fallout, it further
seems pretty clear that all of this is entirely untested and largely
unused.
diff --git a/bfd/coffcode.h b/bfd/coffcode.h
index a2ee036..4a1f4be 100644
--- a/bfd/coffcode.h
+++ b/bfd/coffcode.h
@@ -6133,9 +6133,9 @@
   TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */ \
 									\
   /* Data conversion functions.  */					\
-  bfd_getb64, bfd_getb_signed_64, bfd_putb64,				\
-  bfd_getb32, bfd_getb_signed_32, bfd_putb32,				\
-  bfd_getb16, bfd_getb_signed_16, bfd_putb16,				\
+  bfd_getl64, bfd_getl_signed_64, bfd_putl64,				\
+  bfd_getl32, bfd_getl_signed_32, bfd_putl32,				\
+  bfd_getl16, bfd_getl_signed_16, bfd_putl16,				\
 									\
   /* Header conversion functions.  */					\
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,				\