drm/amdgpu: mark symbols static where possible

We get 7 warnings when building kernel with W=1:
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c:1990:5: warning: no previous prototype for 'amdgpu_pre_soft_reset' [-Wmissing-prototypes]
drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c:1548:5: warning: no previous prototype for 'amdgpu_connector_virtual_dpms' [-Wmissing-prototypes]
drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c:1560:5: warning: no previous prototype for 'amdgpu_connector_virtual_set_property' [-Wmissing-prototypes]
drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c:330:5: warning: no previous prototype for 'amdgpu_cs_list_validate' [-Wmissing-prototypes]
drivers/gpu/drm/amd/amdgpu/dce_virtual.c:98:6: warning: no previous prototype for 'dce_virtual_stop_mc_access' [-Wmissing-prototypes]
drivers/gpu/drm/amd/amdgpu/dce_virtual.c:130:6: warning: no previous prototype for 'dce_virtual_resume_mc_access' [-Wmissing-prototypes]
drivers/gpu/drm/amd/amdgpu/dce_virtual.c:136:6: warning: no previous prototype for 'dce_virtual_set_vga_render_state' [-Wmissing-prototypes]

In fact, all of the functions are only used in the file
in which they are declared and don't need a declaration,
but can be made static.

So this patch marks both functions with 'static'.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NBaoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c

@@ -1545,7 +1545,8 @@ static int amdgpu_connector_virtual_mode_valid(struct drm_connector *connector,
 	return MODE_OK;
 }
 
-int amdgpu_connector_virtual_dpms(struct drm_connector *connector, int mode)
+static int
+amdgpu_connector_virtual_dpms(struct drm_connector *connector, int mode)
 {
 	return 0;
 }
@@ -1557,7 +1558,8 @@ amdgpu_connector_virtual_detect(struct drm_connector *connector, bool force)
 	return connector_status_connected;
 }
 
-int amdgpu_connector_virtual_set_property(struct drm_connector *connector,
+static int
+amdgpu_connector_virtual_set_property(struct drm_connector *connector,
 				  struct drm_property *property,
 				  uint64_t val)
 {

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -2078,7 +2078,7 @@ static bool amdgpu_check_soft_reset(struct amdgpu_device *adev)
 	return asic_hang;
 }
 
-int amdgpu_pre_soft_reset(struct amdgpu_device *adev)
+static int amdgpu_pre_soft_reset(struct amdgpu_device *adev)
 {
 	int i, r = 0;
 

drivers/gpu/drm/amd/amdgpu/dce_virtual.c

@@ -95,7 +95,7 @@ static bool dce_virtual_is_display_hung(struct amdgpu_device *adev)
 	return false;
 }
 
-void dce_virtual_stop_mc_access(struct amdgpu_device *adev,
+static void dce_virtual_stop_mc_access(struct amdgpu_device *adev,
 			      struct amdgpu_mode_mc_save *save)
 {
 	switch (adev->asic_type) {
@@ -127,13 +127,13 @@ void dce_virtual_stop_mc_access(struct amdgpu_device *adev,
 
 	return;
 }
-void dce_virtual_resume_mc_access(struct amdgpu_device *adev,
+static void dce_virtual_resume_mc_access(struct amdgpu_device *adev,
 				struct amdgpu_mode_mc_save *save)
 {
 	return;
 }
 
-void dce_virtual_set_vga_render_state(struct amdgpu_device *adev,
+static void dce_virtual_set_vga_render_state(struct amdgpu_device *adev,
 				    bool render)
 {
 	return;