power: suspend: Add suspend timeout handler

Add suspend timeout handler to prevent device stuck during suspend/
resume process. Suspend timeout handler will dump disk sleep task
at first round timeout and trigger kernel panic at second round timeout.
The default timer for each round is 30 seconds.

Note: Can use following command to simulate suspend hang for testing.
    adb shell echo 1 > /sys/power/pm_hang
    adb shell echo mem > /sys/power/state

Bug: 132733612
Change-Id: Ifc8aa4ee9145187d14511e29529ba50a4b19324e
Signed-off-by: josephjang <josephjang@google.com>
5 files changed