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/rtkit/template

@@ -4,7 +4,7 @@ version=0.10
 revision=2
 homepage="http://git.0pointer.de/?p=rtkit.git"
 distfiles="http://0pointer.de/public/$pkgname-$version.tar.gz"
-build_style=gnu_configure
+build_style=gnu-configure
 configure_args="--with-systemdsystemunitdir=/lib/systemd/system"
 short_desc="Realtime Policy and Watchdog Daemon"
 maintainer="Juan RP <xtraeme@gmail.com>"