ci/deqp-runner: set android rust target in the caller (debian/x86_64_test-android.sh)

This also allows non-x86 android which I hope to add some day.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27420>

.gitlab-ci/container/build-deqp-runner.sh

@@ -27,7 +27,7 @@ else
     DEQP_RUNNER_CARGO_ARGS="--version ${DEQP_RUNNER_VERSION} ${EXTRA_CARGO_ARGS} -- deqp-runner"
 fi
 
-if [ -z "$ANDROID_NDK_HOME" ]; then
+if [[ "$RUST_TARGET" != *-android ]]; then
     cargo install --locked  \
         -j ${FDO_CI_CONCURRENT:-4} \
         --root /usr/local \
@@ -43,10 +43,10 @@ else
         --root /usr/local --version 2.10.0 \
         cargo-ndk
 
-    rustup target add x86_64-linux-android
-    RUSTFLAGS='-C target-feature=+crt-static' cargo ndk --target x86_64-linux-android build --release
+    rustup target add $RUST_TARGET
+    RUSTFLAGS='-C target-feature=+crt-static' cargo ndk --target $RUST_TARGET build --release
 
-    mv target/x86_64-linux-android/release/deqp-runner /deqp-runner
+    mv target/$RUST_TARGET/release/deqp-runner /deqp-runner
 
     cargo uninstall --locked  \
         --root /usr/local \

.gitlab-ci/container/debian/x86_64_test-android.sh

@@ -41,6 +41,7 @@ rm "$ndk.zip"
 ############### Build dEQP runner
 
 export ANDROID_NDK_HOME=/$ndk
+export RUST_TARGET=x86_64-linux-android
 . .gitlab-ci/container/build-rust.sh
 . .gitlab-ci/container/build-deqp-runner.sh