ext4 crypto: enable encryption feature flag

Also add the test dummy encryption mode flag so we can more easily
test the encryption patches using xfstests.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/ialloc.c

@@ -998,7 +998,8 @@ got:
 
 	/* If the directory encrypted, then we should encrypt the inode. */
 	if ((S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) &&
-	    ext4_encrypted_inode(dir))
+	    (ext4_encrypted_inode(dir) ||
+	     DUMMY_ENCRYPTION_ENABLED(sbi)))
 		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
 
 	ext4_set_inode_flags(inode);