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_UnaryFunction1D.h

@@ -37,12 +37,12 @@ extern "C" {
 
 extern PyTypeObject UnaryFunction1D_Type;
 
-#define BPy_UnaryFunction1D_Check(v) (PyObject_IsInstance((PyObject *)v, (PyObject *)&UnaryFunction1D_Type))
+#define BPy_UnaryFunction1D_Check(v) \
+  (PyObject_IsInstance((PyObject *)v, (PyObject *)&UnaryFunction1D_Type))
 
 /*---------------------------Python BPy_UnaryFunction1D structure definition----------*/
 typedef struct {
-	PyObject_HEAD
-	PyObject *py_uf1D;
+  PyObject_HEAD PyObject *py_uf1D;
 } BPy_UnaryFunction1D;
 
 /*---------------------------Python BPy_UnaryFunction1D visible prototypes-----------*/