powerpc/mpc512x: add MPC5125 reset module support for system restart

Only part of MPC5125 reset module is like as MPC5121.
In detail, RCWH register doesn't contain informations about:
- PCI arbiter
- NAND flash page size
- NAND flash port size

For this reason, in device tree, this module has a different name then
MPC5121 reset module but use the same "struct mpc512x_reset_module"
register definition and the same restart procedure.

Signed-off-by: Matteo Facchinetti <[e-mail]>
Signed-off-by: Anatolij Gustschin <[e-mail]>

arch/powerpc/platforms/512x/mpc512x.h

···
 extern void __init mpc512x_setup_arch(void);
 extern int __init mpc5121_clk_init(void);
 extern const char *mpc512x_select_psc_compat(void);
+extern const char *mpc512x_select_reset_compat(void);
 extern void mpc512x_restart(char *cmd);
 
 #endif				/* __MPC512X_H__ */

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

···
 static void __init mpc512x_restart_init(void)
 {
 	struct device_node *np;
+	const char *reset_compat;
 
-	np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-reset");
+	reset_compat = mpc512x_select_reset_compat();
+	np = of_find_compatible_node(NULL, NULL, reset_compat);
 	if (!np)
 		return;
 
···
 
 	if (of_machine_is_compatible("fsl,mpc5125"))
 		return "fsl,mpc5125-psc";
+
+	return NULL;
+}
+
+const char *mpc512x_select_reset_compat(void)
+{
+	if (of_machine_is_compatible("fsl,mpc5121"))
+		return "fsl,mpc5121-reset";
+
+	if (of_machine_is_compatible("fsl,mpc5125"))
+		return "fsl,mpc5125-reset";
 
 	return NULL;
 }