uwb: event_size should be signed

event_size should be ssize_t to notice when hwarc_get_event_size() returns
-ENOSPC.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Vrabel <david.vrabel@csr.com>

drivers/uwb/hwa-rc.c

@@ -501,7 +501,7 @@ int hwarc_filter_event_WUSB_0100(struct uwb_rc *rc, struct uwb_rceb **header,
 	int result = -ENOANO;
 	struct uwb_rceb *rceb = *header;
 	int event = le16_to_cpu(rceb->wEvent);
-	size_t event_size;
+	ssize_t event_size;
 	size_t core_size, offset;
 
 	if (rceb->bEventType != UWB_RC_CET_GENERAL)