codegen: Drop useless comma expression in GType module
codegen: Drop useless comma expression in GType module

jessevdk/vala,frida/vala,kamanashisroy/aroop,tjol/vala-tjol,flobrosch/vala-fixes,severinh/vala,playya/vala,flobrosch/vala-fixes,Distrotech/vala,frida/vala,Distrotech/vala,GNOME/vala,spidermonkdust/vala,frida/vala,rvu95/vala,spidermonkdust/vala,xdave/pvala,flobrosch/vala-fixes,GNOME/vala,severinh/vala,spidermonkdust/vala,kamanashisroy/aroop,Distrotech/vala,jessevdk/vala,jessevdk/vala,GNOME/vala,kamanashisroy/aroop,rvu95/vala,tjol/vala-tjol,playya/vala,playya/vala,rvu95/vala,severinh/vala,frida/vala,frida/vala,GNOME/vala,tjol/vala-tjol