Fix byte swapping bug in get_next_inode_full()

Fix byte swapping bug in get_next_inode_full()

On big-endian systems, while swapping, ext2fs_swap_inode_full() swaps
only 128+extra_isize bytes and the EAs if they are present. Now if inode
N has EAs, (and this is the inode in the "scratch inode") then inode N+1
also carries seems to have them since the "scratch inode" was never
zeroed.

Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>