remote: remove unused constant for libvirtd config file

The LIBVIRTD_CONFIGURATION_FILE constant was introduced in

  commit b7c42619
  Author: Richard W.M. Jones <rjones@redhat.com>
  Date:   Mon Jun 11 11:43:41 2007 +0000

    Mon Jun 11 12:41:00 BST 2007 Richard W.M. Jones <rjones@redhat.com>

and then never used !
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

src/remote/remote_driver.h

@@ -34,7 +34,6 @@ unsigned long remoteVersion(void);
 #define LIBVIRTD_PRIV_UNIX_SOCKET LOCALSTATEDIR "/run/libvirt/libvirt-sock"
 #define LIBVIRTD_PRIV_UNIX_SOCKET_RO LOCALSTATEDIR "/run/libvirt/libvirt-sock-ro"
 #define LIBVIRTD_USER_UNIX_SOCKET "libvirt-sock"
-#define LIBVIRTD_CONFIGURATION_FILE SYSCONFDIR "/libvirt/libvirtd.conf"
 
 /* Defaults for PKI directory. */
 #define LIBVIRT_PKI_DIR SYSCONFDIR "/pki"