tmpfiles.d: skip x11.conf unless --enable-x11-common-plugin

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

Author: troglobit

tmpfiles.d/Makefile.am

@@ -2,10 +2,14 @@ finitdir              = $(finit_tmpfiles)
 dist_finit_DATA       = finit.conf
 
 tmpfilesdir           = $(tmpfiles_path)
-dist_tmpfiles_DATA    = etc.conf legacy.conf var.conf x11.conf
+dist_tmpfiles_DATA    = etc.conf legacy.conf var.conf
 dist_tmpfiles_DATA   += dnsmasq.conf frr.conf lldpd.conf openswan.conf \
 			quagga.conf sshd.conf uuidd.conf
 
 if BUILD_TESTSERV_PLUGIN
 dist_tmpfiles_DATA   += testserv.conf
 endif
+
+if BUILD_X11_COMMON_PLUGIN
+dist_tmpfiles_DATA   += x11.conf
+endif