Fixes for unpredictable nops and 26-bit versions of teq,tst,cmn,cmp.

Fixes for unpredictable nops and 26-bit versions of teq,tst,cmn,cmp.

opcodes * arm-dis.c (print_insn_arm): Disassembling for all targets V6
	and higher with ARM instruction set will now mark the 26-bit
	versions of teq,tst,cmn and cmp as UNPREDICTABLE.
	(arm_opcodes): Fix for unpredictable nop being recognized as a teq.

test    * gas/arm/nops.d: New.
	* gas/arm/nops.s: New.
	* gas/arm/inst.d: Changed expectation file for 26-bit  teq,
	tst, cmn and cmp.