drm/amd/display: "Enable IPS by default"

[Why]
IPS was temporary disabled due to instability.
It was fixed in dmub firmware and with:
- "drm/amd/display: Add IPS checks before dcn register access"
- "drm/amd/display: Disable ips before dc interrupt setting"

[How]
Enable IPS by default.
Disable IPS if 0x800 bit set in amdgpu.dcdebugmask module params

Signed-off-by: Roman Li <Roman.Li@amd.com>
Tested-by: Mark Broadworth <mark.broadworth@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Author: Roman Li

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

@@ -1719,7 +1719,8 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 	init_data.nbio_reg_offsets = adev->reg_offset[NBIO_HWIP][0];
 	init_data.clk_reg_offsets = adev->reg_offset[CLK_HWIP][0];
 
-	init_data.flags.disable_ips = DMUB_IPS_DISABLE_ALL;
+	if (amdgpu_dc_debug_mask & DC_DISABLE_IPS)
+		init_data.flags.disable_ips = DMUB_IPS_DISABLE_ALL;
 
 	init_data.flags.disable_ips_in_vpb = 1;