[ARM] Add ARMv8.3 VJCVT instruction

[Nick Clifton]

Hi Szabolcs,

> gas/
> 2016-12-05  Szabolcs Nagy  <szabolcs.nagy@arm.com>
> 
> 	* config/tc-arm.c (arm_ext_v8_3, do_vjcvt): Define.
> 	(insns): Add vjcvt.
> 
> opcodes/
> 2016-12-05  Szabolcs Nagy  <szabolcs.nagy@arm.com>
> 	* arm-dis.c (coprocessor_opcodes): Add vjcvt.
> 
> gas/testsuite/
> 2016-12-05  Szabolcs Nagy  <szabolcs.nagy@arm.com>
> 
> 	* gas/aarch64/armv8_3-a-fp.s: New.
> 	* gas/aarch64/armv8_3-a-fp.d: New.
> 	* gas/aarch64/armv8_3-a-fp-bad.s: New.
> 	* gas/aarch64/armv8_3-a-fp-bad.d: New.
> 	* gas/aarch64/armv8_3-a-fp-bad.l: New.

Approved - please apply.

Cheers
  Nick