ClangFormat: apply to source, most of intern

Apply clang format as proposed in T53211.

For details on usage and instructions for migrating branches
without conflicts, see:

https://wiki.blender.org/wiki/Tools/ClangFormat

source/blender/freestyle/intern/python/BPy_Iterator.h

@@ -41,15 +41,13 @@ extern PyTypeObject Iterator_Type;
 
 /*---------------------------Python BPy_Iterator structure definition----------*/
 typedef struct {
-	PyObject_HEAD
-	Iterator *it;
+  PyObject_HEAD Iterator *it;
 } BPy_Iterator;
 
 /*---------------------------Python BPy_Iterator visible prototypes-----------*/
 
 int Iterator_Init(PyObject *module);
 
-
 ///////////////////////////////////////////////////////////////////////////////////////////
 
 #ifdef __cplusplus