* config/i386/*aix*, i386aix-nat.c: New files.

	* config/i386/*aix*, i386aix-nat.c: New files.
	* configure.in: Use them.
	* alldeps.mak: List them.
	* coffread.c (decode_base_type): Deal with anonymous enum type.
	* i387-tdep.c (print_387_status_word): Add comment re "top".
	* i386-tdep.c [I386_AIX_TARGET] (i386_extract_return_value): New func.
	* dbxread.c: Use SEEK_SET and SEEK_CUR, not L_*.  Define them if and
	only if not defined by a header file.
	* mipsread.c: Don't define L_SET or L_INCR.