x86_64: Fix the rex prefix for movzxb, movsxb, movb

This patch sets the rex prefix for the source byte register of
movzxb, movsxb, and movb that has the destination memory operand,
when the register is SPL, BPL, SIL, DIL.

This patch adds tests for movzxb and movsxb via Repeatrb(),
and adds the tertiary and quaternary register views for word and
byte registers on x86_64.
TODO: Support tests with memory operands.

Change-Id: I0c5c727f3dd4a75af039b87f7e57d0741e689038
Signed-off-by: Chao-ying Fu <chao-ying.fu@intel.com>
3 files changed