AGESA: Consolidate platform_once() call

Change-Id: I13d8df330db925b2eced7c123ca9926fb259646d
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/20621
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

src/cpu/amd/agesa/family15rl/romstage.c

@@ -21,11 +21,6 @@
 #include <northbridge/amd/agesa/state_machine.h>
 #include <northbridge/amd/agesa/agesa_helper.h>
 
-void platform_once(struct sysinfo *cb)
-{
-	board_BeforeAgesa(cb);
-}
-
 void agesa_main(struct sysinfo *cb)
 {
 	post_code(0x37);

src/cpu/amd/agesa/family15tn/romstage.c

@@ -22,11 +22,6 @@
 #include <northbridge/amd/agesa/state_machine.h>
 #include <northbridge/amd/agesa/agesa_helper.h>
 
-void platform_once(struct sysinfo *cb)
-{
-	board_BeforeAgesa(cb);
-}
-
 void agesa_main(struct sysinfo *cb)
 {
 	post_code(0x37);

src/cpu/amd/agesa/family16kb/romstage.c

@@ -21,11 +21,6 @@
 #include <northbridge/amd/agesa/state_machine.h>
 #include <northbridge/amd/agesa/agesa_helper.h>
 
-void platform_once(struct sysinfo *cb)
-{
-	board_BeforeAgesa(cb);
-}
-
 void agesa_main(struct sysinfo *cb)
 {
 	post_code(0x37);

src/cpu/amd/agesa/romstage.c

@@ -33,6 +33,11 @@ void asmlinkage early_all_cores(void)
 	amd_initmmio();
 }
 
+void __attribute__((weak)) platform_once(struct sysinfo *cb)
+{
+	board_BeforeAgesa(cb);
+}
+
 static void fill_sysinfo(struct sysinfo *cb)
 {
 	memset(cb, 0, sizeof(*cb));