x86_64: remove extra extern declaring about dmi_ioremap

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-x86_64/dmi.h

@@ -3,9 +3,6 @@
 
 #include <asm/io.h>
 
-extern void *dmi_ioremap(unsigned long addr, unsigned long size);
-extern void dmi_iounmap(void *addr, unsigned long size);
-
 #define DMI_MAX_DATA 2048
 
 extern int dmi_alloc_index;