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/gvfs/template

@@ -2,7 +2,7 @@
 pkgname=gvfs
 version=1.10.1
 distfiles="${GNOME_SITE}/$pkgname/1.10/$pkgname-$version.tar.xz"
-build_style=gnu_configure
+build_style=gnu-configure
 configure_args="--disable-hal --disable-afc
 --with-bash-completion-dir=/etc/bash_completion.d"
 short_desc="Userspace virtual filesystem"