Allow bit-patterns in the immediate field of ARM neon mov instructions.

Allow bit-patterns in the immediate field of ARM neon mov instructions.

	* config/tc-arm.c (do_neon_mov): When converting an integer
	immediate into a floating point value, check that the conversion
	is valid.  Also warn if the immediate is valid as both a floating
	point value and a bit pattern.
	* testsuite/gas/arm/vfp-mov-enc.s: Add instructions that use
	floating point bit patterns.
	* testsuite/gas/arm/vfp-mov-enc.d: Add regexps for the disassembly
	of the new insns.