[Clang][ARM] Reenable arm_acle.c test.

This test was apparently disabled in 6fcd4e0, without any
sign of how it was going to be reenabled. This patch rewrites the test
to use update_cc_test_checks, with midend optimizations other that
mem2reg disabled.

The first attempt of this patch in 5ae949a failed on bots even
though it worked locally.  I've attempted to adjust the RUN lines and
made the test AArch64/ARM specific.

Differential Revision: https://reviews.llvm.org/D98510

Author: davemgreen