Revert duplicate "mm/hugetlb.c must #include <asm/io.h>"

This reverts commit 7cb93181, since we
did that patch twice, and the problem was already fixed earlier by
78a34ae2.
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb.c

@@ -17,7 +17,7 @@
 #include <linux/mutex.h>
 #include <linux/bootmem.h>
 #include <linux/sysfs.h>
-#include <asm/io.h>
+
 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/io.h>