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/bluez/template

@@ -3,7 +3,7 @@ pkgname=bluez
 version=4.94
 revision=1
 distfiles="${KERNEL_SITE}/bluetooth/$pkgname-$version.tar.bz2"
-build_style=gnu_configure
+build_style=gnu-configure
 configure_args="--libexecdir=/lib --enable-gstreamer
 --enable-alsa --enable-usb --enable-tools --enable-bccmd
 --enable-hid2hci --enable-dfutool --enable-hidd --enable-pand --enable-dund