drm/amdgpu/atom: Send out the full AUX address

AUX addresses are 20 bits long. Send out the entire address instead of
just the low 16 bits.

Port of:
drm/radeon/atom: Send out the full AUX address
to amdgpu
Reviewed-by: NJammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

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

@@ -139,7 +139,8 @@ amdgpu_atombios_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *m
 
 	tx_buf[0] = msg->address & 0xff;
 	tx_buf[1] = msg->address >> 8;
-	tx_buf[2] = msg->request << 4;
+	tx_buf[2] = (msg->request << 4) |
+		((msg->address >> 16) & 0xf);
 	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
 
 	switch (msg->request & ~DP_AUX_I2C_MOT) {