linux-tools: remove systemd build option (#1736)

srcpkgs/linux-tools/files/usbipd.service

@@ -1,9 +0,0 @@
-[Unit]
-Description=USB/IP server
-After=network.target
-
-[Service]
-ExecStart=/usr/bin/usbipd
-
-[Install]
-WantedBy=multi-user.target

srcpkgs/linux-tools/template

@@ -1,7 +1,7 @@
 # Template file for 'linux-tools'
 pkgname=linux-tools
 version=4.0
-revision=3
+revision=4
 wrksrc="linux-${version}"
 short_desc="Linux kernel tools meta-pkg"
 hostmakedepends="flex perl asciidoc xmlto python automake libtool"
@@ -24,7 +24,6 @@ if [ "$XBPS_TARGET_MACHINE" = "i686" -o "$XBPS_TARGET_MACHINE" = "x86_64" ]; the
 fi
 
 nocross=yes
-build_options="systemd"
 
 do_build() {
 	cd ${wrksrc}/tools/perf
@@ -165,9 +164,6 @@ usbip_package() {
 		vmove "usr/share/man/man8/usbip*"
 		vmove usr/lib/modules-load.d/usbip.conf
 		vsv usbipd
-		if [ "$build_option_systemd" ]; then
-			vinstall ${FILESDIR}/usbipd.service 644 usr/lib/systemd/system
-		fi
 	}
 }
 freefall_package() {