[AArch64][AsmParser] error on unexpected SVE predicate type suffix

Summary:
This patch fixes a bug in the assembler that permitted a type suffix on
predicate registers when not expected. For instance, the following was
previously valid:

    faddv h0, p0.q, z1.h

This bug was present in all SVE instructions containing predicates with
no type suffix and no predication form qualifier, i.e. /z or /m. The
latter instructions are already caught with an appropiate error message
by the assembler, e.g.:

            .text
    <stdin>:1:13: error: not expecting size suffix
    cmpne p1.s, p0.b/z, z2.s, 0
                ^

A similar issue for SVE vector registers was fixed in:

  https://reviews.llvm.org/D59636

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D62942

llvm-svn: 362780