package/mpd: disable documentation

Disable documentation which is enabled by default since version 0.22 and
https://github.com/MusicPlayerDaemon/MPD/commit/2e73e605f78d2e6488e34465a8bfa9e4989a057f

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/mpd/mpd.mk

@@ -11,6 +11,7 @@ MPD_SITE = http://www.musicpd.org/download/mpd/$(MPD_VERSION_MAJOR)
 MPD_DEPENDENCIES = host-pkgconf boost
 MPD_LICENSE = GPL-2.0+
 MPD_LICENSE_FILES = COPYING
+MPD_CONF_OPTS = -Ddocumentation=disabled
 
 # Zeroconf support depends on libdns_sd from avahi.
 ifeq ($(BR2_PACKAGE_MPD_AVAHI_SUPPORT),y)