powerpc: Update obsolete comments in setup_32.c about entry conditions

early_init() is called in-place before kernel relocation and using
whatever MMU setup exists at the point the kernel is entered.

machine_init() is called after relocation and after some initial
mapping of PAGE_OFFSET has been established (typically using BATs
on 6xx/7xx/7xxx processors or some form of bolted TLB on others).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/setup_32.c

@@ -62,9 +62,7 @@ int icache_bsize;
 int ucache_bsize;
 
 /*
- * We're called here very early in the boot.  We determine the machine
- * type and call the appropriate low-level setup functions.
- *  -- Cort <cort@fsmlabs.com>
+ * We're called here very early in the boot.
  *
  * Note that the kernel may be running at an address which is different
  * from the address that it was linked at, so we must use RELOC/PTRRELOC
@@ -105,6 +103,10 @@ notrace unsigned long __init early_init(unsigned long dt_ptr)
 
 
 /*
+ * This is run before start_kernel(), the kernel has been relocated
+ * and we are running with enough of the MMU enabled to have our
+ * proper kernel virtual addresses
+ *
  * Find out what kind of machine we're on and save any data we need
  * from the early boot process (devtree is copied on pmac by prom_init()).
  * This is called very early on the boot process, after a minimal