Added missing include of ohm-plugin-log to signaling.h.
Added missing include of ohm-plugin-log to signaling.h.

jusa/ohm-plugins-misc,tswindell/ohm-plugins-misc,jusa/ohm-plugins-misc,maemo-foss/maemo-multimedia-ohm-plugins-misc,tswindell/ohm-plugins-misc,maemo-foss/maemo-multimedia-ohm-plugins-misc,jusa/ohm-plugins-misc,jusa/ohm-plugins-misc,tswindell/ohm-plugins-misc,maemo-foss/maemo-multimedia-ohm-plugins-misc