device-kobo-clara: add mesa-dri-gallium dep (MR 3306)

Mesa dependency was missing causing the screen to stay blank after boot

device/testing/device-kobo-clara/APKBUILD

 # Reference: <https://postmarketos.org/devicepkg>
 pkgname=device-kobo-clara
 pkgdesc="Kobo Clara HD"
-pkgver=0.3
-pkgrel=1
+pkgver=0.4
+pkgrel=0
 url="https://postmarketos.org"
 license="MIT"
 arch="armv7"
 options="!check !archcheck"
 depends="
+	mesa-dri-gallium
 	perl
 	postmarketos-base
 	u-boot-kobo-clara