powerpc/mpc512x: initialize board restart earlier

move the MPC512x restart initialization from the shared init routine
to the shared init_early routine

recent problems in the proc(5) filesystem initialization led to the
situation where the platform's restart routine was invoked yet the
registers required for software reset were not yet available, which
made the board hang instead of reboot
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>

arch/powerpc/platforms/512x/mpc512x_shared.c

@@ -438,6 +438,7 @@ void __init mpc512x_psc_fifo_init(void)
 
 void __init mpc512x_init_early(void)
 {
+	mpc512x_restart_init();
 	if (IS_ENABLED(CONFIG_FB_FSL_DIU))
 		mpc512x_init_diu();
 }
@@ -446,7 +447,6 @@ void __init mpc512x_init(void)
 {
 	mpc5121_clk_init();
 	mpc512x_declare_of_platform_devices();
-	mpc512x_restart_init();
 	mpc512x_psc_fifo_init();
 }