make release: Call distcheck target verify build from tarball

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

Makefile.am

@@ -9,7 +9,7 @@ install-dev:
 	@make -C src install-pkgincludeHEADERS
 
 # Target to run when building a release
-release: dist
+release: distcheck
 	@for file in $(DIST_ARCHIVES); do	\
 		md5sum $$file > ../$$file.md5;	\
 	done