sfc: Return EBUSY for filter insertion on EF10, matching Falcon/Siena

The MC firmware will return error MC_CMD_ERR_ENOSPC if filter
insertion fails due to lack of resources.  The net driver's filter
implementation for Falcon-architecture returns EBUSY.  They should
behave consistently, so for EF10 change ENOSPC to EBUSY.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/sfc/ef10.c

@@ -2259,6 +2259,8 @@ static int efx_ef10_filter_push(struct efx_nic *efx,
 			  outbuf, sizeof(outbuf), NULL);
 	if (rc == 0)
 		*handle = MCDI_QWORD(outbuf, FILTER_OP_OUT_HANDLE);
+	if (rc == -ENOSPC)
+		rc = -EBUSY; /* to match efx_farch_filter_insert() */
 	return rc;
 }