drm/edid: make drm_edid_are_equal() static

drm_edid_are_equal() is only used within drm_edid.c. Make it static. Do
not encourage more uses of struct edid.
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/aa79be9a5d0b08c71b82b86b5a8ff0f332e13c6a.1713259151.git.jani.nikula@intel.comSigned-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/drm_edid.c

@@ -1827,7 +1827,7 @@ static bool edid_block_is_zero(const void *edid)
  * This helper can be used during probing to determine if
  * edid had changed.
  */
-bool drm_edid_are_equal(const struct edid *edid1, const struct edid *edid2)
+static bool drm_edid_are_equal(const struct edid *edid1, const struct edid *edid2)
 {
 	int edid1_len, edid2_len;
 	bool edid1_present = edid1 != NULL;
@@ -1849,7 +1849,6 @@ bool drm_edid_are_equal(const struct edid *edid1, const struct edid *edid2)
 
 	return true;
 }
-EXPORT_SYMBOL(drm_edid_are_equal);
 
 enum edid_block_status {
 	EDID_BLOCK_OK = 0,

include/drm/drm_edid.h

@@ -348,8 +348,6 @@ int drm_edid_to_speaker_allocation(const struct edid *edid, u8 **sadb);
 int drm_av_sync_delay(struct drm_connector *connector,
 		      const struct drm_display_mode *mode);
 
-bool drm_edid_are_equal(const struct edid *edid1, const struct edid *edid2);
-
 int
 drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
 					 const struct drm_connector *connector,