opcodes/

opcodes/
	* ppc-opc.c (insert_sprg, extract_sprg): New Functions.
	(powerpc_operands <SPRG>): Call the above.  Bit field is 5 bits.
	(SPRG_MASK): Delete.
	(XSPRG_MASK): Mask off extra bits now part of sprg field.
        (powerpc_opcodes): Asjust mfsprg and mtsprg to suit new mask.  Move
	mfsprg4..7 after msprg and consolidate.

gas/testsuite
	* gas/ppc/booke.s: Add new m[t,f]sprg testcases.
	* gas/ppc/booke.d: Likewise.