kasan: remove duplicate definition of the macro KASAN_FREE_PAGE

Remove duplicate definition of the macro KASAN_FREE_PAGE in
mm/kasan/kasan.h

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 4986b0a..c242adf 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -7,7 +7,6 @@
 #define KASAN_SHADOW_MASK       (KASAN_SHADOW_SCALE_SIZE - 1)
 
 #define KASAN_FREE_PAGE         0xFF  /* page was freed */
-#define KASAN_FREE_PAGE         0xFF  /* page was freed */
 #define KASAN_PAGE_REDZONE      0xFE  /* redzone for kmalloc_large allocations */
 #define KASAN_KMALLOC_REDZONE   0xFC  /* redzone inside slub object */
 #define KASAN_KMALLOC_FREE      0xFB  /* object was freed (kmem_cache_free/kfree) */