s390/pci: uninline instruction wrappers

Uninline pci related instruction wrappers to de-bloat the code:
add/remove: 15/0 grow/shrink: 2/24 up/down: 1326/-12628 (-11302)

This is especially useful for the inlined pci read and write functions
which are used all over the kernel. Also remove the unused __stpcifc
while at it.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>