clang-12 fails to build the etm4x driver with -fsanitize=array-bounds,
where it decides to unroll certain loops in a way that result in a
C variable getting put into an inline assembly.
Search this build failure and find this is a known issue and there
has been a mail thread discussing it.
https://patchwork.kernel.org/project/linux-arm-kernel/patch/20210429145752.3218324-1-arnd@xxxxxxxxxx/
According to the modification suggestions of this mail thread,
coresight infrastucture has already provided another API that
can replace the function that caused the error.
Used here "csdev_access_read32" to replace the original API
"etm4x_relaxed_read32".
This patch applies to coresight/next
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>