perf/core improvements and fixes:

New features:

- Allow querying and setting .perfconfig variables (Taeung Song)

- Show branch information in callchains (predicted, TSX aborts, loop
  iteractions, etc) (Jin Yao)

Infrastructure:

- Support kbuild's CFLAGS_REMOVE_ in tools/build (Jiri Olsa)

- Plug building jvmti to the main perf Makefile (Jiri Olsa)

Documentation:

- Update Intel PT documentation about context switch events (Arnaldo Carvalho de Melo)

- Fix 'perf record --call-graph dwarf' help/config in builds not linking
  with a unwind library, mentioning that is a possible record option (Rabin Vincent)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=Pjw4
-----END PGP SIGNATURE-----