drm/amd/amdgpu/amdgpu_uvd: Fix some function documentation headers

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

 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c:95: warning: cannot understand function prototype: 'struct amdgpu_uvd_cs_ctx '
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c:555: warning: Function parameter or member 'adev' not described in 'amdgpu_uvd_cs_msg_decode'
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c:1012: warning: Function parameter or member 'ib_idx' not described in 'amdgpu_uvd_ring_parse_cs'
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c:1286: warning: Function parameter or member 'timeout' not described in 'amdgpu_uvd_ring_test_ib'

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c

@@ -87,7 +87,7 @@
 #define UVD_NO_OP				0x03ff
 #define UVD_BASE_SI				0x3800
 
-/**
+/*
  * amdgpu_uvd_cs_ctx - Command submission parser context
  *
  * Used for emulating virtual memory support on UVD 4.2.
@@ -545,8 +545,8 @@ static int amdgpu_uvd_cs_pass1(struct amdgpu_uvd_cs_ctx *ctx)
 /**
  * amdgpu_uvd_cs_msg_decode - handle UVD decode message
  *
+ * @adev: amdgpu_device pointer
  * @msg: pointer to message structure
- * @buf_sizes: returned buffer sizes
  *
  * Peek into the decode message and calculate the necessary buffer sizes.
  */
@@ -1005,6 +1005,7 @@ static int amdgpu_uvd_cs_packets(struct amdgpu_uvd_cs_ctx *ctx,
  * amdgpu_uvd_ring_parse_cs - UVD command submission parser
  *
  * @parser: Command submission parser context
+ * @ib_idx: Which indirect buffer to use
  *
  * Parse the command stream, patch in addresses as necessary.
  */
@@ -1279,6 +1280,7 @@ void amdgpu_uvd_ring_end_use(struct amdgpu_ring *ring)
  * amdgpu_uvd_ring_test_ib - test ib execution
  *
  * @ring: amdgpu_ring pointer
+ * @timeout: timeout value in jiffies, or MAX_SCHEDULE_TIMEOUT
  *
  * Test if we can successfully execute an IB
  */