drm/amd/display: Fix 2nd DPIA encoder Assignment

drm/amd/display: Fix 2nd DPIA encoder Assignment

[HOW & Why]
There seems to be an issue with 2nd DPIA acquiring link encoder for tiled displays.
Solution is to remove check for eng_id before we get first dynamic encoder for it

Reviewed-by: Cruise Hung <cruise.hung@amd.com>
Reviewed-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@amd.com>
Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Stylon Wang <stylon.wang@amd.com>
Signed-off-by: Mustapha Ghaddar <mghaddar@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>