drm/amd/display/dc/dce112/dce112_resource: Make local functions and ones called by reference static

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:620:22: warning: no previous prototype for ‘dce112_link_encoder_create’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:674:32: warning: no previous prototype for ‘dce112_opp_create’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:689:17: warning: no previous prototype for ‘dce112_aux_engine_create’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:727:20: warning: no previous prototype for ‘dce112_i2c_hw_create’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:742:22: warning: no previous prototype for ‘dce112_clock_source_create’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:766:6: warning: no previous prototype for ‘dce112_clock_source_destroy’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:1027:16: warning: no previous prototype for ‘dce112_validate_global’ [-Wmissing-prototypes]
 drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:1205:29: warning: no previous prototype for ‘dce112_resource_cap’ [-Wmissing-prototypes]

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Anthony Koo <Anthony.Koo@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c

@@ -617,7 +617,7 @@ static const struct encoder_feature_support link_enc_feature = {
 		.flags.bits.IS_TPS4_CAPABLE = true
 };
 
-struct link_encoder *dce112_link_encoder_create(
+static struct link_encoder *dce112_link_encoder_create(
 	const struct encoder_init_data *enc_init_data)
 {
 	struct dce110_link_encoder *enc110 =
@@ -671,7 +671,7 @@ static struct input_pixel_processor *dce112_ipp_create(
 	return &ipp->base;
 }
 
-struct output_pixel_processor *dce112_opp_create(
+static struct output_pixel_processor *dce112_opp_create(
 	struct dc_context *ctx,
 	uint32_t inst)
 {
@@ -686,7 +686,7 @@ struct output_pixel_processor *dce112_opp_create(
 	return &opp->base;
 }
 
-struct dce_aux *dce112_aux_engine_create(
+static struct dce_aux *dce112_aux_engine_create(
 	struct dc_context *ctx,
 	uint32_t inst)
 {
@@ -724,7 +724,7 @@ static const struct dce_i2c_mask i2c_masks = {
 		I2C_COMMON_MASK_SH_LIST_DCE110(_MASK)
 };
 
-struct dce_i2c_hw *dce112_i2c_hw_create(
+static struct dce_i2c_hw *dce112_i2c_hw_create(
 	struct dc_context *ctx,
 	uint32_t inst)
 {
@@ -739,7 +739,7 @@ struct dce_i2c_hw *dce112_i2c_hw_create(
 
 	return dce_i2c_hw;
 }
-struct clock_source *dce112_clock_source_create(
+static struct clock_source *dce112_clock_source_create(
 	struct dc_context *ctx,
 	struct dc_bios *bios,
 	enum clock_source_id id,
@@ -763,7 +763,7 @@ struct clock_source *dce112_clock_source_create(
 	return NULL;
 }
 
-void dce112_clock_source_destroy(struct clock_source **clk_src)
+static void dce112_clock_source_destroy(struct clock_source **clk_src)
 {
 	kfree(TO_DCE110_CLK_SRC(*clk_src));
 	*clk_src = NULL;
@@ -1024,7 +1024,7 @@ enum dc_status dce112_add_stream_to_ctx(
 	return result;
 }
 
-enum dc_status dce112_validate_global(
+static enum dc_status dce112_validate_global(
 		struct dc *dc,
 		struct dc_state *context)
 {
@@ -1202,7 +1202,7 @@ static void bw_calcs_data_update_from_pplib(struct dc *dc)
 	dm_pp_notify_wm_clock_changes(dc->ctx, &clk_ranges);
 }
 
-const struct resource_caps *dce112_resource_cap(
+static const struct resource_caps *dce112_resource_cap(
 	struct hw_asic_id *asic_id)
 {
 	if (ASIC_REV_IS_POLARIS11_M(asic_id->hw_internal_rev) ||