sfc: Remove filter table IDs from filter functions

The separation between filter tables is largely an internal detail
and it may be removed in future hardware.  To prepare for that:

- Merge table ID with filter index to make an opaque filter ID
- Wrap efx_filter_table_clear() with a function that clears filters
  from both RX tables, which is all that the current caller requires

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
diff --git a/drivers/net/sfc/efx.h b/drivers/net/sfc/efx.h
index 10a1bf4..003fdb3 100644
--- a/drivers/net/sfc/efx.h
+++ b/drivers/net/sfc/efx.h
@@ -74,9 +74,8 @@
 				    bool replace);
 extern int efx_filter_remove_filter(struct efx_nic *efx,
 				    struct efx_filter_spec *spec);
-extern void efx_filter_table_clear(struct efx_nic *efx,
-				   enum efx_filter_table_id table_id,
-				   enum efx_filter_priority priority);
+extern void efx_filter_clear_rx(struct efx_nic *efx,
+				enum efx_filter_priority priority);
 
 /* Channels */
 extern void efx_process_channel_now(struct efx_channel *channel);