Fix warning in clad CMakeLists.txt

Fixes the following warning:
```
CMake Warning (dev) in interpreter/cling/tools/plugins/clad/CMakeLists.txt:
  A logical block opening on the line

    /root/root_src/interpreter/cling/tools/plugins/clad/CMakeLists.txt:17 (if)

  closes on the line

    /root/root_src/interpreter/cling/tools/plugins/clad/CMakeLists.txt:27 (endif)

  with mis-matching arguments.
This warning is for project developers.  Use -Wno-dev to suppress it.
```

tools/plugins/clad/CMakeLists.txt

@@ -24,7 +24,7 @@ if(MSVC AND NOT CMAKE_GENERATOR MATCHES Ninja)
     set(CLAD_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${ASAN_EXTRA_CXX_FLAGS}")
   endif()
   set(EXTRA_BUILD_ARGS --config ${_clad_build_type})
-endif(MSVC)
+endif()
 if(NOT _clad_build_type STREQUAL "" AND NOT _clad_build_type STREQUAL ".")
   set(EXTRA_BUILD_ARGS --config ${_clad_build_type})
 endif()