ext2: drop unneeded newline

ext2_msg prints a newline at the end of the message string, so the message
string does not need to include a newline explicitly.  Done using
Coccinelle.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Jan Kara <jack@suse.cz>