arm: Don't disable interrupts during WFE fixup

Disabling interrupts during the Krait WFE fixup can result
in deadlock if a thread tries to acquire a spinlock that is
released from an interrupt context. Instead of disabling
interrupts, modify the interrupt handler to reset the fixup
condition to put the processor into a safe state in the
event that the interrupt came in during the fixup window.

CRs-Fixed: 383670
Change-Id: Id504f46d6f840dc32ca11ed2f813003143e60f2d
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>