REVERT:
From c9650c0bb7324c32d82fa6d7d898e236f10ea63b Mon Sep 17 00:00:00 2001
From: Richard Hughes <richard@hughsie.com>
Date: Mon, 24 Jul 2017 14:30:12 +0100
Subject: [PATCH] Make udev a hard requirement

Index: src/meson.build
--- src/meson.build.orig
+++ src/meson.build
@@ -30,6 +30,11 @@ if get_option('systemd')
   colord_extra_deps += libsystemd
 endif
 
+colord_extra_sources = []
+if get_option('udev_rules')
+  colord_extra_sources += 'cd-sensor-client.c'
+endif
+
 executable(
   'colord',
   resources_src,
@@ -49,7 +54,7 @@ executable(
     'cd-profile.c',
     'cd-profile-db.c',
     'cd-sensor.c',
-    'cd-sensor-client.c',
+    colord_extra_sources,
   ],
   include_directories : [
     colord_incdir,
