x86emul: fix PINSRW and adjust other {,V}PINSR*

x86emul: fix PINSRW and adjust other {,V}PINSR*

The use of simd_packed_int together with no further update to op_bytes
has lead to wrong signaling of #GP(0) for PINSRW without a 16-byte
aligned memory operand. Use simd_none instead and override it after
general decoding with simd_other, like is done for the B/D/Q siblings.

While benign, for consistency also use DstImplicit instead of DstReg
in x86_decode_twobyte().

PINSR{B,D,Q} also had a stray (redundant) get_fpu() invocation, which
gets dropped.

For further consistency also
- use src.bytes instead of op_bytes in relevant memcpy() invocations,
- avoid the pointless updating of op_bytes (all we care about later is
  that the value be less than 16).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>