[MTD] replace MTD_RAM with MTD_GENERIC_TYPE

Ram devices get the extra capability of MTD_NO_ERASE - not requiring
an explicit erase before writing to it.  Currently only mtdblock uses
this capability.  Rest of the patch is a simple text replacement.

Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>

drivers/mtd/mtdblock.c

@@ -289,7 +289,7 @@ static int mtdblock_open(struct mtd_blktrans_dev *mbd)
 
 	mutex_init(&mtdblk->cache_mutex);
 	mtdblk->cache_state = STATE_EMPTY;
-	if (mtdblk->mtd->type != MTD_RAM && mtdblk->mtd->erasesize) {
+	if ( !(mtdblk->mtd->flags & MTD_NO_ERASE) && mtdblk->mtd->erasesize) {
 		mtdblk->cache_size = mtdblk->mtd->erasesize;
 		mtdblk->cache_data = NULL;
 	}