mistaken ext4_inode_bitmap for ext4_block_bitmap

In ext4_new_blocks(), one of two ext4_block_bitmap() calls should be
ext4_inode_bitmap() call.  It is not harmful in normal processing, but it
should be fixed.

Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>