KVM: emulate: cleanup decode_modrm

Remove the if conditional - that will help us avoid
an "else initialize to 0" Also, rearrange operators
for slightly better code.

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --cc arch/x86/kvm/emulate.c
Simple merge