runtime: add arm64 version of AES hash code

Rewrite the arm64 AES hashing code from gc assembler to C code using
intrinsics.  The resulting code generates the same hash code for the
same input as the gc code--that doesn't matter as such, but testing it
ensures that the C code does something useful.

Change-Id: Ifea677fa00e28faa789aa36e44d7188f850a5e3d
Reviewed-on: https://go-review.googlesource.com/138535
Reviewed-by: Cherry Zhang <cherryyz@google.com>
1 file changed