Fix build.h dependencies

For Qt builds, the build.h file is moved to build/build.h. For regular
builds, it is moved to obj/build.h. This allows the Qt build to be done
in a different directory than the source, and without interfering with
other builds.

src/makefile.osx

@@ -11,6 +11,7 @@ DEPSDIR=/opt/local
 
 INCLUDEPATHS= \
  -I"$(CURDIR)" \
+ -I"$(CURDIR)"/obj \
  -I"$(DEPSDIR)/include" \
  -I"$(DEPSDIR)/include/db48"
 
@@ -100,8 +101,9 @@ all: bitcoind
 -include obj/*.P
 -include obj-test/*.P
 
-build.h: FORCE
-	@../share/genbuild.sh build.h
+obj/build.h: FORCE
+	../share/genbuild.sh obj/build.h
+version.cpp: obj/build.h
 DEFS += -DHAVE_BUILD_INFO
 
 obj/%.o: %.cpp
@@ -111,7 +113,7 @@ obj/%.o: %.cpp
 	      -e '/^$$/ d' -e 's/$$/ :/' < $(@:%.o=%.d) >> $(@:%.o=%.P); \
 	  rm -f $(@:%.o=%.d)
 
-bitcoind: build.h $(OBJS:obj/%=obj/%)
+bitcoind: $(OBJS:obj/%=obj/%)
 	$(CXX) $(CFLAGS) -o $@ $(LIBPATHS) $^ $(LIBS)
 
 TESTOBJS := $(patsubst test/%.cpp,obj-test/%.o,$(wildcard test/*.cpp))