tools include: Add __sum16 and __wsum definitions.

This adds definitions available in the uapi version.

Explanation:

In the kernel include of types.h the uapi version is included.
In tools the uapi/linux/types.h and linux/types.h are distinct.
For BPF programs a definition of __wsum is needed by the generated
bpf_helpers.h. The definition comes either from a generated vmlinux.h or
from <linux/types.h> that may be transitively included from bpf.h. The
perf build prefers linux/types.h over uapi/linux/types.h for
<linux/types.h>*. To allow tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c
to compile with the same include path used for perf then these
definitions are necessary.

There is likely a wider conversation about exactly how types.h should be
specified and the include order used by the perf build - it is somewhat
confusing that tools/include/uapi/linux/bpf.h is using the non-uapi
types.h.

*see tools/perf/Makefile.config:
...
INC_FLAGS += -I$(srctree)/tools/include/
INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi
INC_FLAGS += -I$(srctree)/tools/include/uapi
...
The include directories are scanned from left-to-right:
https://gcc.gnu.org/onlinedocs/gcc/Directory-Options.html
As tools/include/linux/types.h appears before
tools/include/uapi/linux/types.h then I say it is preferred.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20210307223024.4081067-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>