Fix building of tools/*

Fixes issue 1282

Originally committed as revision 19486 to svn://svn.ffmpeg.org/ffmpeg/trunk

Makefile

@@ -67,8 +67,11 @@ ffserver_g$(EXESUF): FF_LDFLAGS += $(FFSERVERLDFLAGS)
 %_g$(EXESUF): %.o cmdutils.o $(FF_DEP_LIBS)
 	$(LD) $(FF_LDFLAGS) -o $@ $< cmdutils.o $(FF_EXTRALIBS)
 
-tools/%$(EXESUF): tools/%.c
-	$(LD) $(CFLAGS) $(FF_LDFLAGS) -o $@ $< $(FF_EXTRALIBS)
+tools/%$(EXESUF): tools/%.o
+	$(LD) $(FF_LDFLAGS) -o $@ $< $(FF_EXTRALIBS)
+
+tools/%.o: tools.%.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(CC_O) $<
 
 ffplay.o ffplay.d: CFLAGS += $(SDL_CFLAGS)