BUG_ON conversion for fs/reiserfs

This patch converts several if () BUG(); construct to BUG_ON();
which occupies less space, uses unlikely and is safer when
BUG() is disabled. S_ISREG() has no side effects, so the
conversion is safe.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c
index 8b9b131..5240abe 100644
--- a/fs/reiserfs/stree.c
+++ b/fs/reiserfs/stree.c
@@ -1476,9 +1476,7 @@
 	int n_block_size = p_s_sb->s_blocksize;
 	int cut_bytes;
 	BUG_ON(!th->t_trans_id);
-
-	if (n_new_file_size != p_s_inode->i_size)
-		BUG();
+	BUG_ON(n_new_file_size != p_s_inode->i_size);
 
 	/* the page being sent in could be NULL if there was an i/o error
 	 ** reading in the last block.  The user will hit problems trying to