panic: force console_unlock() in panic()

If panic() is called when console is locked,
oops message can't be printed in console.
Especially, android ram_console doesn't have any information in this case.
Thus, console_unlock() in panic() if console is locked.

 Conflicts:
	kernel/panic.c

Change-Id: Ifbac48875ac189c35ed380b67734d0411bed2c08
Signed-off-by: Bongkyu Kim <bongkyu.kim@lge.com>
Signed-off-by: Patrick Tjin <pattjin@google.com>