drm/amd/display: Add hubp clock status in DTN log for Navi

[Why]
For debug purpose, we need to check HUBP_CLOCK_ENABLE in DTN
log debugfs on Navi.

[How]
Add related register read in dcn20_hubp.c.
Signed-off-by: Leo (Hanghong) Ma <hanghong.ma@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hubp.c

@@ -1202,6 +1202,9 @@ void hubp2_read_state_common(struct hubp *hubp)
 			HUBP_TTU_DISABLE, &s->ttu_disable,
 			HUBP_UNDERFLOW_STATUS, &s->underflow_status);
 
+	REG_GET(HUBP_CLK_CNTL,
+			HUBP_CLOCK_ENABLE, &s->clock_en);
+
 	REG_GET(DCN_GLOBAL_TTU_CNTL,
 			MIN_TTU_VBLANK, &s->min_ttu_vblank);