Add more ARM Cortex-R8 regression tests to Clang.

Summary:
This patch adds Clang tests for Cortex-R8 related to FP capabilities and
hardware integer divide.

Reviewers: rengolin, bsmith

Subscribers: aemerson, cfe-commits, rengolin

Differential Revision: http://reviews.llvm.org/D18193

llvm-svn: 263632