Patch Makefiles for --as-needed and properly install into DESTDIR

--- ./Makefile
+++ ./Makefile
@@ -11,6 +11,7 @@ clean:
 
 install:
 	@echo "Installing vnStat..."
+	install -d $(BIN) $(MAN)/man1 $(CRON) $(DESTDIR)/var/lib/vnstat
 
 # move some really old version database(s) if found
 	@if [ -d $(DESTDIR)/var/spool/vnstat ]; \
@@ -41,7 +42,6 @@ install:
 	then install -m 644 cfg/vnstat.conf $(DESTDIR)/etc; \
 	fi
 
-	install -d $(BIN) $(MAN)/man1 $(CRON) $(DESTDIR)/var/lib/vnstat
 	install -s -m 755 src/vnstat $(BIN)
 
 # update man page, gzip it if previous version was done so	
--- ./src/Makefile
+++ ./src/Makefile
@@ -5,7 +5,7 @@ OBJS = ifinfo.o db.o dbaccess.o misc.o cfg.o
 default: vnstat
 
 vnstat: $(OBJS) vnstat.c vnstat.h
-	$(CC) $(CFLAGS) -lm -o vnstat vnstat.c $(OBJS)
+	$(CC) $(CFLAGS) -o vnstat vnstat.c $(OBJS) -lm
 
 ifinfo.o: ifinfo.c ifinfo.h vnstat.h db.h misc.h cfg.h
 	$(CC) $(CFLAGS) -c ifinfo.c