drm/amd/display: Call ATOM_INIT instead of ATOM_ENABLE for DMCUB

[Why]
DMCUB command table doesn't support ATOM_ENABLE/ATOM_DISABLE anymore
so we never end up calling the DCN init path in DMCUB.

[How]
Map ATOM_ENABLE to ATOM_INIT only for DMCUB command table offloading.

Signed-off-by: Nicholas Kazlauskas <[e-mail]>
Reviewed-by: Tony Cheng <[e-mail]>
Acked-by: Bhawanpreet Lakha <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/bios/command_table2.c

···
 	power_gating.header.sub_type = DMUB_CMD__VBIOS_ENABLE_DISP_POWER_GATING;
 	power_gating.power_gating.pwr = *pwr;
 
+	/* ATOM_ENABLE is old API in DMUB */
+	if (power_gating.power_gating.pwr.enable == ATOM_ENABLE)
+		power_gating.power_gating.pwr.enable = ATOM_INIT;
+
 	dc_dmub_srv_cmd_queue(dmcub, &power_gating.header);
 	dc_dmub_srv_cmd_execute(dmcub);
 	dc_dmub_srv_wait_idle(dmcub);