install-deps: Adding gcc for debian based systems

install-deps: Adding gcc for debian based systems

When running install-deps on a minimalistic system, we reach that situation :

dpkg-checkbuilddeps --admindir=/tmp/install-deps.5526 debian/control
    sh: 1: gcc: not found
    dpkg-checkbuilddeps: warning: Couldn't determine gcc system type, falling back to default (native compilation)
    dpkg-checkbuilddeps: error: cannot open /tmp/install-deps.5526/status: No such file or directory

This means that we shall install gcc before calling dpkg-checkbuilddeps.

Signed-off-by: Erwan Velu <erwan@redhat.com>