m68hc11: make some vars type bfd_reloc_code_real_type

m68hc11: make some vars type bfd_reloc_code_real_type

These variables only hold values from the bfd_reloc_code_real_type enum, and
are passed to functions that expect the argument to be of type
bfd_reloc_code_real_type, so it seems to make sense that there type is
bfd_reloc_code_real_type rather than int.

gas/ChangeLog:

2016-05-16  Trevor Saunders  <tbsaunde+binutils@tbsaunde.org>

	* config/tc-m68hc11.c (fixup8): Change variables type from int to
	bfd_reloc_code_real_type where appropriate.
	(fixup16): Likewise.
	(fixup8_xg): Likewise.