drivers: gpu: Mark functions as static in cirrus_mode.c

Mark functions cirrus_set_start_address(), cirrus_encoder_destroy(),
cirrus_vga_get_modes() and cirrus_connector_best_encoder() as static in
drm/cirrus/cirrus_mode.c because they are not used outside this file.

This eliminates the following warnings in drm/cirrus/cirrus_mode.c:
drivers/gpu/drm/cirrus/cirrus_mode.c:105:6: warning: no previous
prototype for ‘cirrus_set_start_address’ [-Wmissing-prototypes]
drivers/gpu/drm/cirrus/cirrus_mode.c:456:6: warning: no previous
prototype for ‘cirrus_encoder_destroy’ [-Wmissing-prototypes]
drivers/gpu/drm/cirrus/cirrus_mode.c:495:5: warning: no previous
prototype for ‘cirrus_vga_get_modes’ [-Wmissing-prototypes]
drivers/gpu/drm/cirrus/cirrus_mode.c:512:21: warning: no previous
prototype for ‘cirrus_connector_best_encoder’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/cirrus/cirrus_mode.c b/drivers/gpu/drm/cirrus/cirrus_mode.c
index adabc3d..58dd900 100644
--- a/drivers/gpu/drm/cirrus/cirrus_mode.c
+++ b/drivers/gpu/drm/cirrus/cirrus_mode.c
@@ -102,7 +102,7 @@
 	return true;
 }
 
-void cirrus_set_start_address(struct drm_crtc *crtc, unsigned offset)
+static void cirrus_set_start_address(struct drm_crtc *crtc, unsigned offset)
 {
 	struct cirrus_device *cdev = crtc->dev->dev_private;
 	u32 addr;
@@ -453,7 +453,7 @@
 {
 }
 
-void cirrus_encoder_destroy(struct drm_encoder *encoder)
+static void cirrus_encoder_destroy(struct drm_encoder *encoder)
 {
 	struct cirrus_encoder *cirrus_encoder = to_cirrus_encoder(encoder);
 	drm_encoder_cleanup(encoder);
@@ -492,7 +492,7 @@
 }
 
 
-int cirrus_vga_get_modes(struct drm_connector *connector)
+static int cirrus_vga_get_modes(struct drm_connector *connector)
 {
 	int count;
 
@@ -509,7 +509,7 @@
 	return MODE_OK;
 }
 
-struct drm_encoder *cirrus_connector_best_encoder(struct drm_connector
+static struct drm_encoder *cirrus_connector_best_encoder(struct drm_connector
 						  *connector)
 {
 	int enc_id = connector->encoder_ids[0];