Remove unused MTD types

Three types are never set or checked for.  Remove.
Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

include/mtd/mtd-abi.h

@@ -28,10 +28,7 @@ struct mtd_oob_buf {
 #define MTD_ROM			2
 #define MTD_NORFLASH		3
 #define MTD_NANDFLASH		4
-#define MTD_PEROM		5
 #define MTD_DATAFLASH		6
-#define MTD_OTHER		14
-#define MTD_UNKNOWN		15
 
 #define MTD_CLEAR_BITS		1       // Bits can be cleared (flash)
 #define MTD_SET_BITS		2       // Bits can be set