x86: unify free_init_pages() and free_initmem()

Impact: unification

This patch introduces a common arch/x86/mm/init.c and moves the identical
free_init_pages() and free_initmem() functions to the file.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <1236078906.2675.18.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index 2b938a3..0853774 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -1,4 +1,4 @@
-obj-y	:=  init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
+obj-y	:=  init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
 	    pat.o pgtable.o gup.o
 
 obj-$(CONFIG_SMP)		+= tlb.o