madvise: correct the comment of MADV_DODUMP flag

s/MADV_NODUMP/MADV_DONTDUMP/

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/uapi/asm-generic/mman-common.h

@@ -50,7 +50,7 @@
 
 #define MADV_DONTDUMP   16		/* Explicity exclude from the core dump,
 					   overrides the coredump filter bits */
-#define MADV_DODUMP	17		/* Clear the MADV_NODUMP flag */
+#define MADV_DODUMP	17		/* Clear the MADV_DONTDUMP flag */
 
 /* compatibility flags */
 #define MAP_FILE	0