ci/deqp: avoid downloading 1.47 GiB multiple times

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32250>

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

@@ -93,10 +93,12 @@ case "${DEQP_API}" in
   GLES) DEQP_VERSION="opengl-es-cts-$DEQP_GLES_VERSION";;
 esac
 
-mkdir /VK-GL-CTS
+mkdir -p /VK-GL-CTS
 pushd /VK-GL-CTS
-git init
-git remote add origin https://github.com/KhronosGroup/VK-GL-CTS.git
+[ -e .git ] || {
+  git init
+  git remote add origin https://github.com/KhronosGroup/VK-GL-CTS.git
+}
 git fetch --depth 1 origin "$DEQP_VERSION"
 git checkout FETCH_HEAD
 DEQP_COMMIT=$(git rev-parse FETCH_HEAD)
@@ -256,7 +258,6 @@ if [ "${DEQP_API}" = 'GLES' ]; then
   ${STRIP_CMD:-strip} modules/*/deqp-*
 fi
 du -sh ./*
-rm -rf /VK-GL-CTS
 popd
 
 section_end deqp-$deqp_api

.gitlab-ci/container/debian/test-gl.sh

@@ -112,6 +112,8 @@ DEQP_API=GLES \
 DEQP_TARGET=surfaceless \
 . .gitlab-ci/container/build-deqp.sh
 
+rm -rf /VK-GL-CTS
+
 ############### Build apitrace
 
 . .gitlab-ci/container/build-apitrace.sh

.gitlab-ci/container/debian/test-vk.sh

@@ -108,6 +108,8 @@ DEQP_API=VK \
 DEQP_TARGET=default \
 . .gitlab-ci/container/build-deqp.sh
 
+rm -rf /VK-GL-CTS
+
 ############### Build apitrace
 
 . .gitlab-ci/container/build-apitrace.sh

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

@@ -60,6 +60,8 @@ DEQP_TARGET="android" \
 EXTRA_CMAKE_ARGS="-DDEQP_TARGET_TOOLCHAIN=ndk-modern -DANDROID_NDK_PATH=/$ndk -DANDROID_ABI=x86_64 -DDE_ANDROID_API=28" \
 . .gitlab-ci/container/build-deqp.sh
 
+rm -rf /VK-GL-CTS
+
 ############### Downloading Cuttlefish resources ...
 
 CUTTLEFISH_VERSION=9082637   # Chosen from https://ci.android.com/builds/branches/aosp-master/grid?

.gitlab-ci/container/lava_build.sh

@@ -305,6 +305,8 @@ DEQP_TARGET=surfaceless \
 DEQP_TARGET=default \
 . .gitlab-ci/container/build-deqp.sh
 
+rm -rf /VK-GL-CTS
+
 mv /deqp $ROOTFS/.