powerpc: Move free_initmem to common code

The free_initmem function is basically duplicated in mm/init_32,
and init_64, and is moved to the common 32/64-bit mm/mem.c.

All other sections except init were removed in v2.6.15 by
6c45ab992e4299c869fb26427944a8f8ea177024 (powerpc: Remove section
free() and linker script bits), and therefore the bulk of the executed
code is identical.

This patch also removes updating ppc_md.progress to NULL in the powermac
late_initcall.

Suggested-by: Milton Miller <miltonm@bga.com>
Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Dave Carroll <dcarroll@astekcorp.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 89cbfef..e9379ce 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -383,6 +383,25 @@
 	mem_init_done = 1;
 }
 
+void free_initmem(void)
+{
+	unsigned long addr;
+
+	ppc_md.progress = NULL;
+
+	addr = (unsigned long)__init_begin;
+	for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
+		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
+		ClearPageReserved(virt_to_page(addr));
+		init_page_count(virt_to_page(addr));
+		free_page(addr);
+		totalram_pages++;
+	}
+	pr_info("Freeing unused kernel memory: %luk freed\n",
+		((unsigned long)__init_end -
+		(unsigned long)__init_begin) >> 10);
+}
+
 #ifdef CONFIG_BLK_DEV_INITRD
 void __init free_initrd_mem(unsigned long start, unsigned long end)
 {