Previous patches have introduced the compiler attribute btf_type_tag for
__user and __percpu. The availability of this attribute depends on
some CONFIGs and compiler support. This patch refactors the use
of btf_type_tag by introducing BTF_TYPE_TAG, which hides all the
dependencies.
No functional change.
Suggested-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Cc: Yonghong Song <yhs@xxxxxx>
Signed-off-by: Hao Luo <haoluo@xxxxxxxxxx>