package/mesa3d: add optional support for libunwind

Added by commit
https://cgit.freedesktop.org/mesa/mesa/commit/?h=17.1&id=70c272004f727457e852ba5f2498754b07a7d995

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/mesa3d/mesa3d.mk

@@ -189,6 +189,13 @@ else
 MESA3D_CONF_OPTS += --disable-xvmc
 endif
 
+ifeq ($(BR2_PACKAGE_LIBUNWIND),y)
+MESA3D_CONF_OPTS += --enable-libunwind
+MESA3D_DEPENDENCIES += libunwind
+else
+MESA3D_CONF_OPTS += --disable-libunwind
+endif
+
 ifeq ($(BR2_PACKAGE_LIBVDPAU),y)
 MESA3D_DEPENDENCIES += libvdpau
 MESA3D_CONF_OPTS += --enable-vdpau