[clang] [clang][ssaf] Add JSONFormat support for WPASuite (PR #187403)

[Balázs Benics via cfe-commits]

================
@@ -0,0 +1,12 @@
+if(LLVM_ENABLE_PLUGINS)
----------------
steakhal wrote:

When I looked at `clang/lib/Analysis/plugins/CMakeLists.txt` it had this guard condition:

```
# Since these do not specify a specific PLUGIN_TOOL (which could be clang or
# clang-tidy), we cannot compile this unless the platform supports plugins with
# undefined symbols, and cannot use it unless the user has opted for clang plugins).
if(CLANG_ENABLE_STATIC_ANALYZER AND CLANG_PLUGIN_SUPPORT AND LLVM_ENABLE_PLUGINS)
  add_subdirectory(SampleAnalyzer)
  add_subdirectory(CheckerDependencyHandling)
  add_subdirectory(CheckerOptionHandling)
endif()
```

  
I wonder if we should also guard on the `CLANG_PLUGIN_SUPPORT` variable.

https://github.com/llvm/llvm-project/pull/187403