RFC: ANDROID: add support for clang Control Flow Integrity (CFI)

This change adds the CONFIG_CFI_CLANG option, CFI error handling,
and a faster look-up table for cross module CFI checks.

Bug: 67506682
Change-Id: Ic009f0a629b552a0eb16e6d89808c7029e91447d
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
[AmitP: Rebased to newer kernels without clang LTO support]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>