SCRIPTS: create-release: show the correct origin name in suggested commands

create-release shows the next steps at the end and suggest to use
"git push origin master" but on my machine it's not "origin" so let's
determine it using git config and only use origin as a fall back.
diff --git a/scripts/create-release b/scripts/create-release
index 4eb1fc1..fe6c802 100755
--- a/scripts/create-release
+++ b/scripts/create-release
@@ -225,8 +225,9 @@
 do_commit || die "Failed to commit changes"
 do_tag    || die "Failed to tag changes"
+remote=$(git config --get branch.master.remote)
 echo "Do not forget to push updates, publish and announce this version :"
-echo "git push origin master v$NEW"
+echo "git push ${remote:-origin} master v$NEW"
 echo "${0%/*}/publish-release"
 echo "${0%/*}/announce-release"