package/yavta: disable -Werror

Fix build failure which is raised since bump to latest version in commit
87ba7be02fdd185668f86a59539343c70e1108e0

Fixes:
 - http://autobuild.buildroot.org/results/d5b4f69f46cef4dd11410fe48d21372cb883ae4a

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

package/yavta/yavta.mk

@@ -9,5 +9,6 @@ YAVTA_SITE = https://git.ideasonboard.org/git/yavta.git
 YAVTA_SITE_METHOD = git
 YAVTA_LICENSE = GPL-2.0+
 YAVTA_LICENSE_FILES = COPYING.GPL
+YAVTA_CONF_OPTS = -Dwerror=false
 
 $(eval $(meson-package))