cpu: Add MPC83xx CPU driver

Add a CPU driver for the MPC83xx architecture.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/arch/powerpc/cpu/mpc83xx/cpu_init.c b/arch/powerpc/cpu/mpc83xx/cpu_init.c
index fcac9f6..1555205 100644
--- a/arch/powerpc/cpu/mpc83xx/cpu_init.c
+++ b/arch/powerpc/cpu/mpc83xx/cpu_init.c
@@ -464,6 +464,7 @@
 }
 #endif /* CONFIG_DISPLAY_AER_xxxx */
 
+#ifndef CONFIG_CPU_MPC83XX
 /*
  * Figure out the cause of the reset
  */
@@ -505,3 +506,4 @@
 
 	return 0;
 }
+#endif