[clang] [clang][analyzer] Split NullDereferenceChecker into a modeling and checker part (PR #122139)

[Donát Nagy via cfe-commits]

================
@@ -206,7 +206,12 @@ def CallAndMessageChecker : Checker<"CallAndMessage">,
   Documentation<HasDocumentation>,
   Dependencies<[CallAndMessageModeling]>;
 
-def DereferenceChecker : Checker<"NullDereference">,
+def DereferenceModeling : Checker<"DereferenceModeling">,
+  HelpText<"General support for dereference related checkers">,
+  Documentation<HasDocumentation>,
+  Hidden;
----------------
NagyDonat wrote:

Is `HasDocumentation` compatible with `Hidden`? My understanding was that `Hidden` checkers are purely implementation details and they don't have their separate documentation.

https://github.com/llvm/llvm-project/pull/122139