Update build_style for all templates.

- There's no need to set build_style for custom-install (default).
- gnu_{configure,makefile} renamed to gnu-{configure,makefile}.

srcpkgs/vte3/template

@@ -3,7 +3,7 @@ pkgname=vte3
 version=0.30.1
 wrksrc=vte-${version}
 distfiles="${GNOME_SITE}/vte/0.30/vte-$version.tar.xz"
-build_style=gnu_configure
+build_style=gnu-configure
 configure_args="--with-gtk=3.0 --enable-introspection
 --disable-gnome-pty-helper"
 short_desc="Terminal widget with improved accessibility and I18N support"