perf symbols: Remove some unnecessary includes from symbol.h

And fixup the fallout in places like annotation and jitdump that were
using things like dirname() but weren't including libgen.h, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-wrii9hy1a1wathc0398f9fgt@git.kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>