tools headers: Adopt verbatim copy of btf_ids.h from kernel sources

It will be needed by bpf selftest for resolve_btfids tool.

Also adding __PASTE macro as btf_ids.h dependency, which is
defined in:

  include/linux/compiler_types.h

but because tools/include do not have this header, I'm putting
the macro into linux/compiler.h header.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-9-jolsa@kernel.org