s390/ap: fix vanishing crypto cards in SE environment

s390/ap: fix vanishing crypto cards in SE environment

A secure execution (SE, also known as confidential computing)
guest may see asynchronous errors on a crypto firmware queue.
The current implementation to gather information about cards
and queues in ap_queue_info() simple returns if an asynchronous
error is hanging on the firmware queue. If such a situation
happened and it was the only queue visible for a crypto card
within an SE guest, then the card vanished from sysfs as
the AP bus scan function refuses to hold a card without any
type information. As lszcrypt evaluates the sysfs such
a card vanished from the lszcrypt card listing and the
user is baffled and has no way to reset and thus clear the
pending asynchronous error.

This patch improves the named function to also evaluate GR2
of the TAPQ in case of asynchronous error pending. If there
is a not-null value stored in, the info is processed now.
In the end, a queue with pending asynchronous error does not
lead to a vanishing card any more.

Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>