x86: split __phys_addr out into separate file

Split __phys_addr out into its own file so we can disable
-fstack-protector in a fine-grained fashion.  Also it doesn't
have terribly much to do with the rest of ioremap.c.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index 72bb3a2..9b5a9f5 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -1,9 +1,9 @@
 obj-y	:=  init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
-	    pat.o pgtable.o gup.o
+	    pat.o pgtable.o physaddr.o gup.o
 
 # Make sure __phys_addr has no stackprotector
 nostackp := $(call cc-option, -fno-stack-protector)
-CFLAGS_ioremap.o		:= $(nostackp)
+CFLAGS_physaddr.o		:= $(nostackp)
 
 obj-$(CONFIG_SMP)		+= tlb.o