powerpc: Drop probecpu() in favour of arch_cpu_init()

To avoid an unnecessary arch-specific call in board_init_f(), rename this
function.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/common.h b/include/common.h
index 2af555e..53cdadf 100644
--- a/include/common.h
+++ b/include/common.h
@@ -600,7 +600,17 @@
 u32	cpu_mask      (void);
 u32	cpu_dsp_mask(void);
 int	is_core_valid (unsigned int);
-int	probecpu      (void);
+
+/**
+ * arch_cpu_init() - basic cpu-dependent setup for an architecture
+ *
+ * This is called after early malloc is available. It should handle any
+ * CPU- or SoC- specific init needed to continue the init sequence. See
+ * board_f.c for where it is called. If this is not provided, a default
+ * version (which does nothing) will be used.
+ */
+int arch_cpu_init(void);
+
 int	checkcpu      (void);
 int	checkicache   (void);
 int	checkdcache   (void);