sfc: Rename Falcon-architecture register definitions

The EF10 architecture has a very different register layout from
previous controllers, so we'll use separate files for the two sets of
register definitions.  Use 'farch' as an abbreviation for
Falcon-architecture.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
diff --git a/drivers/net/ethernet/sfc/siena.c b/drivers/net/ethernet/sfc/siena.c
index f0ae262..d0eeb03 100644
--- a/drivers/net/ethernet/sfc/siena.c
+++ b/drivers/net/ethernet/sfc/siena.c
@@ -19,7 +19,7 @@
 #include "efx.h"
 #include "nic.h"
 #include "spi.h"
-#include "regs.h"
+#include "farch_regs.h"
 #include "io.h"
 #include "phy.h"
 #include "workarounds.h"