Fix compiler warning in lib_ppc/board.c

Fix compiler warning introduced by commit 0f8cbc18

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/board/freescale/mpc8536ds/mpc8536ds.c b/board/freescale/mpc8536ds/mpc8536ds.c
index 3cf12fd..3066b24 100644
--- a/board/freescale/mpc8536ds/mpc8536ds.c
+++ b/board/freescale/mpc8536ds/mpc8536ds.c
@@ -608,7 +608,7 @@
 }
 #endif
 
-int is_sata_supported()
+int is_sata_supported(void)
 {
 	volatile ccsr_gur_t *gur = (void *)(CFG_MPC85xx_GUTS_ADDR);
 	uint devdisr = gur->devdisr;