drm/amd/display: Copy AUX read reply data whenever length > 0

[Why]
amdgpu_dm_process_dmub_aux_transfer_sync() should return all exact data
reply from the sink side. Don't do the analysis job in it.

[How]
Remove unnecessary check condition AUX_TRANSACTION_REPLY_AUX_ACK.

Fixes: ead08b9 ("drm/amd/display: Fix race condition in DPIA AUX transfer")
Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Ray Wu <ray.wu@amd.com>
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -12853,8 +12853,7 @@ int amdgpu_dm_process_dmub_aux_transfer_sync(
 		/* The reply is stored in the top nibble of the command. */
 		payload->reply[0] = (adev->dm.dmub_notify->aux_reply.command >> 4) & 0xF;
 
-	if (!payload->write && p_notify->aux_reply.length &&
-			(payload->reply[0] == AUX_TRANSACTION_REPLY_AUX_ACK))
+	if (!payload->write && p_notify->aux_reply.length)
 		memcpy(payload->data, p_notify->aux_reply.data,
 				p_notify->aux_reply.length);