x86/APX: support extended SETcc form

As indicated during review, spelling/readability-wise

	setz	%eax

is easier than

	setzuz	%al

_and_ properly specifies the full register that's being modified. Permit
that form to be used, even if the spec writers are unwilling to formally
mention it.

While there also correct the non-ZU EVEX form: That ought to also permit
memory operands.