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/southbridge/amd/rs780/cmn.c

@@ -256,9 +256,6 @@ u8 PcieTrainPort(struct device *nb_dev, struct device *dev, u32 port)
 	u32 lc_state, reg, current_link_width, lane_mask;
 	int8_t current, res = 0;
 	u32 gfx_gpp_sb_sel;
-	void set_pcie_dereset(void);
-	void set_pcie_reset(void);
-
 	switch (port) {
 	case 2 ... 3:
 		gfx_gpp_sb_sel = PCIE_CORE_INDEX_GFX;
@@ -397,3 +394,11 @@ int is_family10h(void)
 {
 	return cpuidFamily() == 0x10;
 }
+
+__weak void set_pcie_reset(void)
+{
+}
+
+__weak void set_pcie_dereset(void)
+{
+}

src/southbridge/amd/rs780/gfx.c

@@ -36,9 +36,6 @@
 #include <cpu/x86/msr.h>
 #include "rs780.h"
 
-void set_pcie_reset(void);
-void set_pcie_dereset(void);
-
 /* Trust the original resource allocation. Don't do it again. */
 #undef DONT_TRUST_RESOURCE_ALLOCATION
 //#define DONT_TRUST_RESOURCE_ALLOCATION

src/southbridge/amd/rs780/rs780.h

@@ -223,5 +223,7 @@ void enable_rs780_dev8(void);
 void rs780_early_setup(void);
 void rs780_htinit(void);
 int is_dev3_present(void);
+void set_pcie_reset(void);
+void set_pcie_dereset(void);
 
 #endif /* __RS780_H__ */