jffs2: include <linux/mtd/compat.h> instead of defining own min_t

Include <linux/mtd/compat.h> header for min_t definition instead of
providing our own one. Removes warnings in case of OneNAND support
enabled.

Although I thinks it's a bit silly to include <linux/mtd/compat.h>
just for min_t...

Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Stefan Roese <sr@denx.de>
diff --git a/fs/jffs2/jffs2_1pass.c b/fs/jffs2/jffs2_1pass.c
index be7c1a1..11b66ab 100644
--- a/fs/jffs2/jffs2_1pass.c
+++ b/fs/jffs2/jffs2_1pass.c
@@ -119,6 +119,7 @@
 #include <watchdog.h>
 #include <jffs2/jffs2.h>
 #include <jffs2/jffs2_1pass.h>
+#include <linux/mtd/compat.h>
 
 #include "jffs2_private.h"
 
@@ -1408,11 +1409,6 @@
 }
 #endif
 
-#define min_t(type, x, y) ({                    \
-	type __min1 = (x);                      \
-	type __min2 = (y);                      \
-	__min1 < __min2 ? __min1: __min2; })
-
 #define DEFAULT_EMPTY_SCAN_SIZE	4096
 
 static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size)