BACKPORT: kbuild: gcov: enable -fno-tree-loop-im if supported

Clang does not recognize this compiler option.

Reported-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
(cherry picked from commit c64ba044ed57ea72cc1c7b14a8dcfb6ded5a759c)
Bug: 122733725
Test: defconfig + CONFIG_GCOV_KERNEL records coverage

Change-Id: I334ebf83a9209d1e4a3e29ee12279f36f7afecdd