libusb: Do not use `weak' modifier where it is not applicable
libusb: Do not use `weak' modifier where it is not applicable

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