drm/i915/tc: Fix system hang on ADL-P during TypeC PHY disconnect

drm/i915/tc: Fix system hang on ADL-P during TypeC PHY disconnect

The PHY ownership release->AUX PW disable steps during a modeset
disable->PHY disconnect sequence can hang the system if the PHY
disconnect happens after disabling the PHY's PLL. The spec doesn't
require a specific order for these two steps, so this issue is still
being root caused by HW/FW teams. Until that is found, let's make
sure the disconnect happens before the PLL is disabled, and do this on
all platforms for consistency.

v2: Add a TODO comment to remove the w/a once the issue is root
    caused/fixed. (Jose)

Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210929132833.2253961-7-imre.deak@intel.com