This is currently working due to extra include paths in the build.

Committer testing:

  $ cd tools/include/uapi/asm/

Before this patch:

  $ ls -la ../../arch/x86/include/uapi/asm/errno.h
  ls: cannot access '../../arch/x86/include/uapi/asm/errno.h': No such file or directory
  $

After this patch;

  $ ls -la ../../../arch/x86/include/uapi/asm/errno.h
  -rw-rw-r--. 1 acme acme 31 Feb 20 12:42 ../../../arch/x86/include/uapi/asm/errno.h
  $

Check that that is still under tools/, i.e. hasn't escaped into the main
kernel sources:

  $ cd ../../../arch/x86/include/uapi/asm/
  $ pwd
  /home/acme/git/perf/tools/arch/x86/include/uapi/asm
  $
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexios Zavras <alexios.zavras@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Li <liwei391@huawei.com>
Link: http://lore.kernel.org/lkml/20200306071110.130202-2-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>