drm/amd/display: Prevent IPX From Link Detect and Set Mode

drm/amd/display: Prevent IPX From Link Detect and Set Mode

commit 1ff6631baeb1f5d69be192732d0157a06b43f20a upstream.

IPX involvment proven to affect LT, causing link loss. Need to prevent
IPX enabled in LT process in which link detect and set mode are main
procedures that have LT taken place.

Reviewed-by: Roman Li <roman.li@amd.com>
Acked-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Kevin Holm <kevin@holm.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>