Revert "drivers: power: Add watchdog timer to catch drivers which lockup during suspend."

This reverts commit 4f0d2860.

Commit 70fea60d ("PM / Sleep: Detect device suspend/resume lockup...")
add a suspend/resume watchdog timer to catch the lockup. Let's revert the
duplicated one.

Signed-off-by: Lianwei Wang <lianwei.wang@gmail.com>