s390/ap: new low level inline functions ap_bapq() and ap_aapq()

Introduce two new low level functions ap_bapq() (calls
PQAP(BAPQ)) and ap_aapq (calls PQAP(AAPQ)). Both functions
are only meant to be used in SE environment with the SE
AP binding facility available.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>