pds_core: fix error handling in pdsc_devcmd_wait

pds_core: fix error handling in pdsc_devcmd_wait

Fix two cases where pdsc_devcmd_wait() returns stale success from
the completion register instead of an error:

1. FW crash: If firmware stops running, the wait loop breaks early with
   running=false. The condition "if ((!done || timeout) && running)" is
   false, so error handling is bypassed and stale status is returned.
   Check !running first and return -ENXIO.

2. Timeout: If a command times out, err is set to -ETIMEDOUT but then
   overwritten by pdsc_err_to_errno(status) which reads stale status.
   Return -ETIMEDOUT immediately after cleaning up.

Both errors now propagate to pdsc_devcmd_locked() which queues
health_work for recovery.

Fixes: 45d76f492938 ("pds_core: set up device and adminq")
Signed-off-by: Nikhil P. Rao <nikhil.rao@amd.com>
Link: https://patch.msgid.link/20260515212907.998028-1-nikhil.rao@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>