sb/amd/rs780: Fix invalid function declarations

Provide empty stub implementations for set_pcie_reset() and
set_pcie_dereset(), many boards do not provide a proper one.

Change-Id: Ia6811442905ef1776fa5a8e3f5d4433e86e42f88
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/26776
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/mainboard/iei/kino-780am2-fam10/mainboard.c

@@ -24,21 +24,10 @@
 #include "southbridge/amd/sb700/smbus.h"
 #include "southbridge/amd/rs780/rs780.h"
 
-void set_pcie_dereset(void);
-void set_pcie_reset(void);
 /* TODO - Need to find GPIO for PCIE slot.
  * Kino uses GPIO ? as PCIe slot reset, GPIO? as GFX slot reset. We need to
  * pull it up before training the slot.
  ***/
-void set_pcie_dereset()
-{
-	/* PCIE slot not yet supported.*/
-}
-
-void set_pcie_reset()
-{
-	/* PCIE slot not yet supported.*/
-}
 
 int is_dev3_present(void)
 {