drm/amd/display: New Behavior for debug option disable_ips_in_vpb

drm/amd/display: New Behavior for debug option disable_ips_in_vpb

[Why & How]
To facilitate debugging, the following behaviors are defined for existing
debug option disable_ips_in_vpb

0 - Enable IPS in LVP - let driver decide (legacy)
1 - Disable IPS in LVP
2 - Enable IPS1 and RCG in LVP
3 - Enable IPS1 Z8, IPS1 and RCG in LVP

Reviewed-by: Duncan Ma <duncan.ma@amd.com>
Signed-off-by: Leo Chen <leo.chen@amd.com>
Signed-off-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>