llvmPackages_{12,13,14,15,16,17,18,19,20,git}.llvm: refactor (#389873)

lib/strings.nix

@@ -1849,7 +1849,7 @@ rec {
     : The type of the feature to be set, as described in
       https://cmake.org/cmake/help/latest/command/set.html
       the possible values (case insensitive) are:
-      BOOL FILEPATH PATH STRING INTERNAL
+      BOOL FILEPATH PATH STRING INTERNAL LIST
 
     `value`
     : The desired value
@@ -1872,7 +1872,7 @@ rec {
     :::
   */
   cmakeOptionType = let
-    types = [ "BOOL" "FILEPATH" "PATH" "STRING" "INTERNAL" ];
+    types = [ "BOOL" "FILEPATH" "PATH" "STRING" "INTERNAL" "LIST" ];
   in type: feature: value:
     assert (elem (toUpper type) types);
     assert (isString feature);