Fixed man page installation.

Makefile

@@ -23,6 +23,6 @@ install: all
 
 uninstall:
 	rm -f ${DESTDIR}/${PREFIX}/bin/${PROG}
-	rm -f ${DESTDIR}/${MANPREFIX}/${PROG}.1
+	rm -f ${DESTDIR}/${MANPREFIX}/man1/${PROG}.1
 
 .PHONY: all clean install uninstall