x86: Allow 16-bit register source for LAR and LSL

Since LAR and LSL only access 16 bits of the source operand, regardless
of operand size, allow 16-bit register source for LAR and LSL, and always
disassemble LAR and LSL with 16-bit source operand.

gas/

	PR gas/29844
	* testsuite/gas/i386/i386.s: Add tests for LAR and LSL.
	* testsuite/gas/i386/x86_64.s: Likewise.
	* testsuite/gas/i386/intelbad.s: Remove "lar/lsl eax, ax".
	* testsuite/gas/i386/i386-intel.d: Updated.
	* testsuite/gas/i386/i386.d: Likewise.
	* testsuite/gas/i386/intel-intel.d: Likewise.
	* testsuite/gas/i386/intel.d: Likewise.
	* testsuite/gas/i386/intelbad.l: Likewise.
	* testsuite/gas/i386/x86_64-intel.d: Likewise.
	* testsuite/gas/i386/x86_64.d: Likewise.

opcodes/

	PR gas/29844
	* i386-dis.c (MOD_0F02): Removed.
	(MOD_0F03): Likewise.
	(dis386_twobyte): Restore larS and lslS.
	(mod_table): Remove MOD_0F02 and MOD_0F03.
	* i386-opc.tbl: Allow 16-bit register source for LAR and LSL.
	* i386-tbl.h: Regenerated.