target-xtensa: fix guest hang on masked CCOMPARE interrupt

target-xtensa: fix guest hang on masked CCOMPARE interrupt

QEMU timer is used to post CCOMPARE interrupt when the core is halted.
If that CCOMPARE interrupt is masked off then the timer must be rearmed
in the callback, otherwise it will be rearmed next time the core goes to
halt by the waiti instruction.

Add test case into timer testsuite.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>