mm/mmap: kill hook arch_rebalance_pgtables()

Nobody uses it.
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/mmap.c

@@ -55,10 +55,6 @@
 #define arch_mmap_check(addr, len, flags)	(0)
 #endif
 
-#ifndef arch_rebalance_pgtables
-#define arch_rebalance_pgtables(addr, len)		(addr)
-#endif
-
 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
 const int mmap_rnd_bits_min = CONFIG_ARCH_MMAP_RND_BITS_MIN;
 const int mmap_rnd_bits_max = CONFIG_ARCH_MMAP_RND_BITS_MAX;
@@ -1911,7 +1907,6 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
 	if (offset_in_page(addr))
 		return -EINVAL;
 
-	addr = arch_rebalance_pgtables(addr, len);
 	error = security_mmap_addr(addr);
 	return error ? error : addr;
 }