perf event: Remove needless include directives from event.h

bpf.h and build-id.h are not needed at all in event.h, remove them.

And fixup the fallout of files that were getting needed stuff from this
now pruned include.

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-rdm3dgtlrndmmnlc4bafsg3b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/powerpc/util/unwind-libdw.c

@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <elfutils/libdwfl.h>
+#include <linux/kernel.h>
 #include "../../util/unwind-libdw.h"
 #include "../../util/perf_regs.h"
 #include "../../util/event.h"