Remove dead code which contains bad gettext block

Remove dead code which contains bad gettext block

Found this dead code when I examine gettext messages in shell scripts
start with dash ('-' or '--'). An error will be raised for this case,
like:

    $ gettext "-d option is no longer supported.  Do not use."
    gettext: missing arguments

Indead, this code has been left as dead for a long time, as Jonathan
points out:

    The git am -d/--dotest option has errored out with a message
    since e72c7406 (am: remove support for -d .dotest, 2008-03-04).
    The error message about lack of support was eliminated along
    with other cleanups (probably by mistake) a year later by
    removing the option from the option table in 98ef23b3 (git-am:
    minor cleanups, 2009-01-28).

    But the code to handle -d and --dotest stayed around even though
    ever since then it could not be tripped.  Remove this dead code.

Signed-off-by: Jiang Xin <worldhello.net@gmail.com>
Reviewed-by: Stefano Lattarini <stefano.lattarini@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>