drm: Replace filp in ioctl arguments with drm_file *file_priv.

As a fallout, replace filp storage with file_priv storage for "unique
identifier of a client" all over the DRM.  There is a 1:1 mapping, so this
should be a noop.  This could be a minor performance improvement, as everyth
on Linux dereferenced filp to get file_priv anyway, while only the mmap ioct
went the other direction.

Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/r300_cmdbuf.c b/drivers/char/drm/r300_cmdbuf.c
index 669aee6..59b2944 100644
--- a/drivers/char/drm/r300_cmdbuf.c
+++ b/drivers/char/drm/r300_cmdbuf.c
@@ -780,8 +780,7 @@
  * Called by the ioctl handler function radeon_cp_cmdbuf.
  */
 int r300_do_cp_cmdbuf(struct drm_device *dev,
-		      DRMFILE filp,
-		      struct drm_file *filp_priv,
+		      struct drm_file *file_priv,
 		      drm_radeon_kcmd_buffer_t *cmdbuf)
 {
 	drm_radeon_private_t *dev_priv = dev->dev_private;
@@ -884,9 +883,10 @@
 			}
 
 			buf = dma->buflist[idx];
-			if (buf->filp != filp || buf->pending) {
+			if (buf->file_priv != file_priv || buf->pending) {
 				DRM_ERROR("bad buffer %p %p %d\n",
-					  buf->filp, filp, buf->pending);
+					  buf->file_priv, file_priv,
+					  buf->pending);
 				ret = -EINVAL;
 				goto cleanup;
 			}