build: Fix sbase-box-install target

The target tried to execute a non valid shell script
and there was a possibility to fatorize the creation
of the proto file instead of repeating it in all
the actions that required.

Makefile

@@ -220,18 +220,19 @@ getconf.o: getconf.h
 getconf.h:
 	scripts/getconf.sh > $@
 
-install uninstall:
+proto: $(BIN)
 	scripts/mkproto $(DESTDIR)$(PREFIX) $(DESTDIR)$(MANPREFIX) proto
+
+install uninstall: proto
 	scripts/$@ proto
 
-sbase-box-install: sbase-box
-	scripts/mkproto $(DESTDIR)$(PREFIX) $(DESTDIR)$(MANPREFIX) proto
-	scripts/$@ proto
+sbase-box-install: sbase-box proto
+	scripts/install proto
 	$(DESTDIR)$(PREFIX)/bin/sbase-box -i $(DESTDIR)$(PREFIX)/bin/
 
-sbase-box-uninstall: sbase-box
+sbase-box-uninstall: sbase-box proto
 	$(DESTDIR)$(PREFIX)/bin/sbase-box -d $(DESTDIR)$(PREFIX)/bin/
-	$(MAKE) uninstall
+	scripts/uninstall proto
 
 dist: clean
 	mkdir -p sbase-$(VERSION)

scripts/mkbox

@@ -61,6 +61,7 @@ install(char *path)
 			        bp->name);
 			exit(1);
 		}
+		remove(fname);
 		if (symlink("sbase-box", fname) < 0) {
 			fprintf(stderr,
 			        "sbase-box: %s: %s\n",