Add `-Wl,-z,defs` in `%cflags` to make linking more consistent across
distros. Aims to catch typos in handwritten assembly tests. If
intentional, individual tests can override this with: `-Wl,-z,undefs`
Tests changed:
- bolt/test/AArch64/bf_min_alignment.s: fixed a typo
- bolt/test/AArch64/tls.c: overriding behaviour in all clang
invocations, making the test more consistent.
- Overrides to allow undefined symbols in:
- bolt/test/AArch64/epilogue-determination.s
- bolt/test/AArch64/exceptions-plt.cpp
- bolt/test/AArch64/ifunc.test
- bolt/test/AArch64/plt-call.test
- bolt/test/AArch64/text-data.c
- bolt/test/AArch64/unsupported-passes.test
- bolt/test/AArch64/unsupported-passes.test
242fcb3556