cudaPackages.markForCudatoolkitRootHook: fix bug with strictDeps

The setupCudaHook always checks for the existence of `$prefix/nix-support/include-in-cudatoolkit-root`, so we need to be sure
it always exists. It isn't populated when `strictDeps` is set, but it must exist.

pkgs/development/cuda-modules/setup-hooks/mark-for-cudatoolkit-root-hook.sh

@@ -1,14 +1,25 @@
 # shellcheck shell=bash
 
-# Should we mimick cc-wrapper's "hygiene"?
-[[ -z ${strictDeps-} ]] || (( "$hostOffset" < 0 )) || return 0
+(( ${hostOffset:?} == -1 && ${targetOffset:?} == 0)) || return 0
 
 echo "Sourcing mark-for-cudatoolkit-root-hook" >&2
 
 markForCUDAToolkit_ROOT() {
-    mkdir -p "${prefix}/nix-support"
-    [[ -f "${prefix}/nix-support/include-in-cudatoolkit-root" ]] && return 0
-    echo "$pname-$output" > "${prefix}/nix-support/include-in-cudatoolkit-root"
+    mkdir -p "${prefix:?}/nix-support"
+    local markerPath="$prefix/nix-support/include-in-cudatoolkit-root"
+
+    # Return early if the file already exists.
+    [[ -f "$markerPath" ]] && return 0
+
+    # Always create the file, even if it's empty, since setup-cuda-hook relies on its existence.
+    # However, only populate it if strictDeps is not set.
+    touch "$markerPath"
+
+    # Return early if strictDeps is set.
+    [[ -n "${strictDeps-}" ]] && return 0
+
+    # Populate the file with the package name and output.
+    echo "${pname:?}-${output:?}" > "$markerPath"
 }
 
 fixupOutputHooks+=(markForCUDAToolkit_ROOT)