s390/zcrypt: improve special ap message cmd handling

There exist very few ap messages which need to have the 'special' flag
enabled. This flag tells the firmware layer to do some pre- and maybe
postprocessing. However, it may happen that this special flag is
enabled but the firmware is unable to deal with this kind of message
and thus returns with reply code 0x41. For example older firmware may
not know the newest messages triggered by the zcrypt device driver and
thus react with reject and the named reply code. Unfortunately this
reply code is not known to the zcrypt error routines and thus default
behavior is to switch the ap queue offline.

This patch now makes the ap error routine aware of the reply code and
so userspace is informed about the bad processing result but the queue
is not switched to offline state any more.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/uapi/asm/zcrypt.h

@@ -150,8 +150,8 @@ struct ica_xcRB {
  * @cprb_len:		CPRB header length [0x0020]
  * @cprb_ver_id:	CPRB version id.   [0x04]
  * @pad_000:		Alignment pad bytes
- * @flags:		Admin cmd [0x80] or functional cmd [0x00]
- * @func_id:		Function id / subtype [0x5434]
+ * @flags:		Admin bit [0x80], Special bit [0x20]
+ * @func_id:		Function id / subtype [0x5434] "T4"
  * @source_id:		Source id [originator id]
  * @target_id:		Target id [usage/ctrl domain id]
  * @ret_code:		Return code