Long ago we decided to be verbotten including files in the kernel git
sources from tools/ living source code, to avoid disturbing kernel
development (and perf's and other tools/) when, say, a kernel hacker
adds something, tests everything but tools/ and have tools/ build
broken.

This got broken recently by s/390, fix it by copying
arch/s390/include/uapi/asm/perf_regs.h to tools/arch/s390/include/uapi/asm/,
making this one be used by means of <asm/perf_regs.h> and updating
tools/perf/check_headers.sh to make sure we are notified when the
original changes, so that we can check if anything is needed on the
tooling side.

This would have been caught by the 'tarkpg' test entry in:

$ make -C tools/perf build-test

When run on a s/390 build system or container.
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: f704ef44 ("s390/perf: add support for perf_regs and libdw")
Link: https://lkml.kernel.org/n/tip-n57139ic0v9uffx8wdqi3d8a@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>