pylibfdt: Use package_dir to set the package directory

At present we manually move _libfdt.so into the correct place. Provide a
package directory so we can avoid needing to do this.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

pylibfdt/Makefile.pylibfdt

@@ -7,9 +7,8 @@ PYMODULE = $(PYLIBFDT_objdir)/_libfdt.so
 
 $(PYMODULE): $(PYLIBFDT_srcs) $(WRAP)
 	@$(VECHO) PYMOD $@
-	SOURCES="$^" CPPFLAGS="$(CPPFLAGS)" \
+	SOURCES="$^" CPPFLAGS="$(CPPFLAGS)" OBJDIR="$(PYLIBFDT_objdir)" \
 	python $(PYLIBFDT_objdir)/setup.py --quiet build_ext --inplace
-	mv _libfdt.so $(PYMODULE)
 
 $(WRAP): $(PYLIBFDT_srcdir)/libfdt.swig
 	@$(VECHO) SWIG $@