drm/amd/display: use unsigned types for local pipe and REG_GET counters

Two small type fixes that match how the values are actually consumed:

- decide_zstate_support() iterates from 0 to pipe_count, which is
  unsigned. Make the loop index unsigned int.

- hpo_enc401_read_state() reads HDMI_PIXEL_ENCODING and
  HDMI_DEEP_COLOR_DEPTH via REG_GET_2(), which internally casts the
  output pointer to (uint32_t *). Passing the address of an int is a
  strict-aliasing wart even when the sizes match. Declare the locals
  as uint32_t.

No behavioural change since the values are only compared against small
non-negative constants.

Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml/dcn20/dcn20_fpu.c

@@ -1060,7 +1060,7 @@ static bool is_dtbclk_required(struct dc *dc, struct dc_state *context)
 static enum dcn_zstate_support_state  decide_zstate_support(struct dc *dc, struct dc_state *context)
 {
 	int plane_count;
-	int i;
+	unsigned int i;
 
 	plane_count = 0;
 	for (i = 0; i < dc->res_pool->pipe_count; i++) {

drivers/gpu/drm/amd/display/dc/hpo/dcn401/dcn401_hpo_frl_stream_encoder.c

@@ -143,8 +143,8 @@ void hpo_enc401_read_state(
 	struct hpo_frl_stream_encoder *enc,
 	struct hpo_frl_stream_encoder_state *state)
 {
-	int pixel_encoding;
-	int color_depth;
+	uint32_t pixel_encoding;
+	uint32_t color_depth;
 //	int odm_combine;
 	struct dcn401_hpo_frl_stream_encoder *enc401 = DCN401_HPO_FRL_STRENC_FROM_HPO_FRL_STRENC(enc);