s390x: Replace unchecked qdev_init() by qdev_init_nofail()

s390x: Replace unchecked qdev_init() by qdev_init_nofail()

s390_flic_init() is a helper to create and realize either
"s390-flic-kvm" or "s390-flic-qemu".  When qdev_init() fails, it
complains to stderr and succeeds.

Except it can't actually fail, because the "s390-flic-qemu" is a dummy
without a realize method, and "s390-flic-kvm"'s realize can't fail,
even when the kernel device is really unavailable.  Odd.

Replace qdev_init() by qdev_init_nofail() to make "can't fail" locally
obvious, and get rid of the unreachable error reporting.

Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-Id: <1423128889-18260-4-git-send-email-armbru@redhat.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>