Only print prefixes before fwait

gas/testsuite/

	* gas/i386/prefix.s: Add another fwait test.
	* gas/i386/prefix.d: Updated.

opcodes/

	* i386-dis.c (fwait_prefix): New.
	(ckprefix): Set fwait_prefix.
	(print_insn): Properly print prefixes before fwait.
Wrap PyObject_Get/HasAttrString in a function with second arg having const qualifier.

This is done to avoid errors when compiled with -Werror against Python-2.4
which did not have the const qualifier for the second argument of these
functions.

gdb/
	* python/python-internal.h (gdb_PyObject_GetAttrString)
	(gdb_PyObject_HasAttrString): New inline function definitions.
	* py-value.c (get_field_flag): Remove the now unnecessary cast to
	char * of the second argument to PyObject_GetAttrString.