Fix art_quick_instrumentation_exit for ARM64

Stores the integer result in x0 into the stack. Also avoids clobbering integer
result in x0 by setting it to xSELF after copying it to x2 when calling the
artInstrumentationMethodExitFromCode function.

Bug: 15690361
Change-Id: I9fb873cf32f194779f299607dda8a7316a99c528
1 file changed