Clean up ifdef logic for finding the exception table via libdl versus static linker resolution.

Change-Id: I05800e26d6e15f4cc1c3a35e6bf97360ba72f9e0
Switch define from HAS_DLFCN to IS_BAREMETAL.

Change-Id: I5d0b6f4be3a3a573787f08198b839f028496e991
Make sure dlfcn can be included even if not ARMEHABI

Change-Id: I46c0a2b273597d811b4b5cab1caee52a57e8383d
Merge pull request #95 from awong-dev/lidbdl_ifdef_cleanup

Clean up ifdef logic for finding exidx via libdl versus static linker resolution.