s390/zcrypt: remove duplicate low level functions

ap_test_queue, ap_query_facilities, __ap_query_functions all use
the same PQAP(TAPQ) command. Consolidate the three into a single
ap_test_queue function that returns the AP status and the 64-bit
result. The exception table entry for PQAP(TAPQ) can be avoided
if the T bit for the APFT facility is set only if test_facility(15)
indicated that the facility is present.

Integrate ap_query_function into ap_query queue to avoid calling
PQAP(TAPQ) twice.

Reviewed-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>