mpc512x: remove dead code

The prt_mpc512x_clks() function isn't referenced
anywhere and its prototype is wrong. Remove it.
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

arch/powerpc/cpu/mpc512x/speed.c

@@ -151,9 +151,3 @@ U_BOOT_CMD(clocks, 1, 0, do_clocks,
 	"print clock configuration",
 	"    clocks"
 );
-
-int prt_mpc512x_clks (void)
-{
-	do_clocks (NULL, 0, 0, NULL);
-	return (0);
-}

include/common.h

@@ -648,9 +648,6 @@ int	prt_8260_clks (void);
 #elif defined(CONFIG_MPC5xxx)
 int	prt_mpc5xxx_clks (void);
 #endif
-#if defined(CONFIG_MPC512X)
-int	prt_mpc512xxx_clks (void);
-#endif
 #if defined(CONFIG_MPC8220)
 int	prt_mpc8220_clks (void);
 #endif