spectrwm: fix config files location

spectrwm will search in this order:

- XDG_CONFIG_HOME
- $HOME/.spectrwm.conf
- XDG_CONFIG_DIRS
- /etc/spectrwm.conf
- $HOME/.scrotwm.conf
- /etc/scrotwm.conf

Nowhere it searchs in /usr/etc

srcpkgs/spectrwm/template

@@ -1,11 +1,11 @@
 # Template file for 'spectrwm'
 pkgname=spectrwm
 version=3.4.1
-revision=2
+revision=3
 _distname=SPECTRWM_${version//./_}
 wrksrc="spectrwm-${_distname}"
 build_style=gnu-makefile
-make_build_args='-C linux'
+make_build_args='-C linux SYSCONFDIR=/etc'
 make_install_args="$make_build_args"
 hostmakedepends="pkg-config"
 makedepends="libXcursor-devel libXft-devel libXrandr-devel libXt-devel
@@ -16,6 +16,7 @@ license="ISC"
 homepage="http://spectrwm.org"
 distfiles="https://github.com/conformal/spectrwm/archive/${_distname}.tar.gz"
 checksum=c030ef30bd11bbdfce3d4a1daf51f0c1358821ba95ebdc4cdb32d3944c8ce03c
+conf_files="/etc/spectrwm.conf"
 
 if [ "$XBPS_TARGET_LIBC" = "musl" ]; then
 	makedepends+=" musl-legacy-compat"