GWN: Port to GPU module: Move files to GPU

This does not include all the struct and type renaming. Only files were
renamed.

gwn_batch.c/h was fusioned with GPU_batch.c/h
gwn_immediate.c/h was fusioned with GPU_immediate.c/h
gwn_imm_util.c/h was fusioned with GPU_immediate_util.c/h

source/blender/gpu/intern/gpu_primitive_private.h

@@ -0,0 +1,37 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2016 by Mike Erwin.
+ * All rights reserved.
+ *
+ * Contributor(s): Blender Foundation
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/gpu/gwn_primitive_private.h
+ *  \ingroup gpu
+ *
+ * Gawain geometric primitives
+ */
+
+#ifndef __GWN_PRIMITIVE_PRIVATE_H__
+#define __GWN_PRIMITIVE_PRIVATE_H__
+
+GLenum convert_prim_type_to_gl(Gwn_PrimType);
+
+#endif /* __GWN_PRIMITIVE_PRIVATE_H__ */