x86: Disable GOT relaxation with data prefix

x86: Disable GOT relaxation with data prefix

Since linker GOT relaxation isn't valid for 16-bit GOT access, we should
disable GOT relaxation with data prefix.

gas/

	PR gas/r23854
	* config/tc-i386.c (output_disp): Disable GOT relaxation with
	data prefix.
	* testsuite/gas/i386/mixed-mode-reloc32.d: Updated.

ld/

	PR gas/r23854
	* testsuite/ld-i386/i386.exp: Run pr23854.
	* testsuite/ld-x86-64/x86-64.exp: Likewwise.
	* testsuite/ld-i386/pr23854.d: New file.
	* testsuite/ld-i386/pr23854.s: Likewwise.
	* testsuite/ld-i386/pr23854.d: Likewwise.
	* testsuite/ld-x86-64/pr23854.d: Likewwise.
	* testsuite/ld-x86-64/pr23854.s: Likewwise.