nfsd4: rearrange struct nfsd4_slot

Combine two booleans into a single flag field, move the smaller fields
to the end.

(In practice this doesn't make the struct any smaller.  But we'll be
adding another flag here soon.)

Remove some debugging code that doesn't look useful, while we're in the
neighborhood.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 0ec5a1b..279a705 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3532,7 +3532,7 @@
 	if (length > session->se_fchannel.maxresp_sz)
 		return nfserr_rep_too_big;
 
-	if (slot->sl_cachethis == 1 &&
+	if ((slot->sl_flags & NFSD4_SLOT_CACHETHIS) &&
 	    length > session->se_fchannel.maxresp_cached)
 		return nfserr_rep_too_big_to_cache;
 
@@ -3656,8 +3656,7 @@
 	if (nfsd4_has_session(cs)) {
 		if (cs->status != nfserr_replay_cache) {
 			nfsd4_store_cache_entry(resp);
-			dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__);
-			cs->slot->sl_inuse = false;
+			cs->slot->sl_flags &= ~NFSD4_SLOT_INUSE;
 		}
 		/* Renew the clientid on success and on replay */
 		release_session_client(cs->session);