drm/radeon: Move radeon_ttm{init, fini} to shared location

Fixes the following W=1 kernel build warning(s):

drivers/gpu/drm/radeon/radeon_ttm.c: At top level:
drivers/gpu/drm/radeon/radeon_ttm.c:817:5: warning: no previous prototype for ‘radeon_ttm_init’ [-Wmissing-prototypes]
817 | int radeon_ttm_init(struct radeon_device *rdev)
| ^~~~~~~~~~~~~~~
drivers/gpu/drm/radeon/radeon_ttm.c:878:6: warning: no previous prototype for ‘radeon_ttm_fini’ [-Wmissing-prototypes]
878 | void radeon_ttm_fini(struct radeon_device *rdev)
| ^~~~~~~~~~~~~~~

Cc: Alex Deucher <[e-mail]>
Cc: "Christian König" <[e-mail]>
Cc: David Airlie <[e-mail]>
Cc: Daniel Vetter <[e-mail]>
Cc: Sumit Semwal <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Lee Jones <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/radeon/radeon_object.c

···
 
 #include "radeon.h"
 #include "radeon_trace.h"
+#include "radeon_ttm.h"
 
-int radeon_ttm_init(struct radeon_device *rdev);
-void radeon_ttm_fini(struct radeon_device *rdev);
 static void radeon_bo_clear_surface_reg(struct radeon_bo *bo);
 
 /*

drivers/gpu/drm/radeon/radeon_ttm.c

···
 
 #include "radeon_reg.h"
 #include "radeon.h"
+#include "radeon_ttm.h"
 
 static int radeon_ttm_debugfs_init(struct radeon_device *rdev);
 static void radeon_ttm_debugfs_fini(struct radeon_device *rdev);

drivers/gpu/drm/radeon/radeon_ttm.h

···
+/* radeon_ttm.h -- Private header for radeon driver -*- linux-c -*-
+ *
+ * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
+ * Copyright 2000 VA Linux Systems, Inc., Fremont, California.
+ * All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#ifndef __RADEON_TTM_H__
+#define __RADEON_TTM_H__
+
+struct radeon_device;
+
+int radeon_ttm_init(struct radeon_device *rdev);
+void radeon_ttm_fini(struct radeon_device *rdev);
+
+#endif				/* __RADEON_TTM_H__ */