fuse: optimize over-io-uring request expiration check

Currently, when checking whether a request has timed out, we check
fpq processing, but fuse-over-io-uring has one fpq per core and 256
entries in the processing table. For systems where there are a
large number of cores, this may be too much overhead.

Instead of checking the fpq processing list, check ent_w_req_queue
and ent_in_userspace.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Bernd Schubert <bernd@bsbernd.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>