ci/init-stage2: set VK_DRIVER_FILES for both xorg and wayland

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29201>

.gitlab-ci/common/init-stage2.sh

@@ -158,6 +158,9 @@ if [ -x /capture-devcoredump.sh ]; then
   BACKGROUND_PIDS="$! $BACKGROUND_PIDS"
 fi
 
+ARCH=$(uname -m)
+export VK_DRIVER_FILES="/install/share/vulkan/icd.d/${VK_DRIVER}_icd.$ARCH.json"
+
 # If we want Xorg to be running for the test, then we start it up before the
 # HWCI_TEST_SCRIPT because we need to use xinit to start X (otherwise
 # without using -displayfd you can race with Xorg's startup), but xinit will eat
@@ -165,7 +168,6 @@ fi
 if [ -n "$HWCI_START_XORG" ]; then
   echo "touch /xorg-started; sleep 100000" > /xorg-script
   env \
-    VK_DRIVER_FILES="/install/share/vulkan/icd.d/${VK_DRIVER}_icd.$(uname -m).json" \
     xinit /bin/sh /xorg-script -- /usr/bin/Xorg -noreset -s 0 -dpms -logfile /Xorg.0.log &
   BACKGROUND_PIDS="$! $BACKGROUND_PIDS"
 
@@ -192,7 +194,6 @@ if [ -n "$HWCI_START_WESTON" ]; then
   mkdir -p /tmp/.X11-unix
 
   env \
-    VK_DRIVER_FILES="/install/share/vulkan/icd.d/${VK_DRIVER}_icd.$(uname -m).json" \
     weston -Bheadless-backend.so --use-gl -Swayland-0 --xwayland --idle-time=0 &
   BACKGROUND_PIDS="$! $BACKGROUND_PIDS"