Remove old workaround for unsupported Ubuntu.
Remove old workaround for unsupported Ubuntu.

Ubuntu 7.04 is almost 8 years old now. This workaround can and should be
removed. It was added by fcc9ba4b99aee39ca1555bde458f0933d4797d53.

Change-Id: Ic5d393bfd36e48a193fcffff13b90dc453eb1652
Reviewed-by: hjk <4622a3e4640ee19ab4ebad197849e45b7170d50c@theqtcompany.com>
Reviewed-by: Christian Kandeler <3aa99dcdd3f0cac61fb81c2a11771c0cc2497607@theqtcompany.com>

kuba1/qtcreator,amyvmiwei/qt-creator,danimo/qt-creator,amyvmiwei/qt-creator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,martyone/sailfish-qtcreator,kuba1/qtcreator,danimo/qt-creator,xianian/qt-creator,danimo/qt-creator,Distrotech/qtcreator,Distrotech/qtcreator,danimo/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,martyone/sailfish-qtcreator,kuba1/qtcreator,kuba1/qtcreator,Distrotech/qtcreator,Distrotech/qtcreator,xianian/qt-creator,xianian/qt-creator,martyone/sailfish-qtcreator,danimo/qt-creator,amyvmiwei/qt-creator,xianian/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,kuba1/qtcreator,kuba1/qtcreator,xianian/qt-creator,martyone/sailfish-qtcreator,Distrotech/qtcreator,kuba1/qtcreator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,danimo/qt-creator,danimo/qt-creator,Distrotech/qtcreator,danimo/qt-creator,danimo/qt-creator,amyvmiwei/qt-creator,kuba1/qtcreator,xianian/qt-creator,xianian/qt-creator,kuba1/qtcreator,amyvmiwei/qt-creator,Distrotech/qtcreator,martyone/sailfish-qtcreator