dev-cpp/ETL: update upstream metadata

Signed-off-by: Luca Barbato <[email protected]>

Author: lu-zero

dev-cpp/ETL/metadata.xml

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE pkgmetadata SYSTEM "https://www.gentoo.org/dtd/metadata.dtd">
 <pkgmetadata>
-    <!-- maintainer-needed -->
+	<!-- maintainer-needed -->
 	<upstream>
-		<remote-id type="sourceforge">synfig</remote-id>
+		<remote-id type="github">synfig/synfig</remote-id>
 	</upstream>
 </pkgmetadata>