community/device-asus-me176c: install vulkan/libva driver if needed (MR 3195)

Add subpackages that automatically cause installation of the Vulkan
and libva driver if packages using them get installed. This reduces
the size of a minimal rootfs but still ensures those are present if
needed.

[ci:skip-build]: already built successfully in CI

device/community/device-asus-me176c/APKBUILD

@@ -2,8 +2,8 @@
 # Maintainer: Minecrell <minecrell@minecrell.net>
 pkgname=device-asus-me176c
 pkgdesc="ASUS MeMO Pad 7 (ME176C(X))"
-pkgver=4
-pkgrel=1
+pkgver=5
+pkgrel=0
 _commit=3155254999ac36c3051a2118c415de25a072c0f6
 url="https://postmarketos.org"
 license="MIT"
@@ -16,7 +16,6 @@ depends="
 	intel-ucode
 	linux-asus-me176c
 	mesa-dri-classic
-	mesa-vulkan-intel
 	postmarketos-base
 	"
 makedepends="devicepkg-dev meson eudev-dev"
@@ -24,7 +23,13 @@ source="https://github.com/me176c-dev/linux-me176c/archive/$_commit.tar.gz
 	deviceinfo
 	phoc.ini
 	"
-subpackages="$pkgname-factory $pkgname-nonfree-firmware:nonfree_firmware $pkgname-phosh"
+subpackages="
+	$pkgname-factory
+	$pkgname-nonfree-firmware:nonfree_firmware
+	$pkgname-phosh
+	$pkgname-vulkan
+	$pkgname-libva
+	"
 builddir="$srcdir/linux-me176c-$_commit"
 
 build() {
@@ -60,6 +65,18 @@ phosh() {
 		"$subpkgdir"/etc/phosh/phoc.ini
 }
 
+vulkan() {
+	install_if="$pkgname vulkan-loader"
+	depends="mesa-vulkan-intel"
+	mkdir "$subpkgdir"
+}
+
+libva() {
+	install_if="$pkgname libva"
+	depends="libva-intel-driver"
+	mkdir "$subpkgdir"
+}
+
 sha512sums="
 75243e3d0bc9a352465683ec8cf8b83566e4131bb7fae0f388267a62bdbf4691c955ed034b30df550f921b771080688123ae8db144b72f786bf1677ef1d83f57  3155254999ac36c3051a2118c415de25a072c0f6.tar.gz
 c8bb189b08035e647e07dec120a6e166d871c17a227987387228c8bf6ff264e029f950c69bb560d3062cee0e27e4fb93449523592558108690a82c6d40931de1  deviceinfo