drm/panel: Include <linux/export.h>

Fix the compile-time warnings

  drivers/gpu/drm/drm_panel.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
  drivers/gpu/drm/drm_panel_backlight_quirks.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
  drivers/gpu/drm/drm_panel_orientation_quirks.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
  drivers/gpu/drm/panel/panel-samsung-s6e63m0.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: a934a57a42 ("scripts/misc-check: check missing #include <linux/export.h> when W=1")
Reviewed-by: André Almeida <andrealmeid@igalia.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250612121633.229222-8-tzimmermann@suse.de

drivers/gpu/drm/drm_panel.c

@@ -23,6 +23,7 @@
 
 #include <linux/backlight.h>
 #include <linux/err.h>
+#include <linux/export.h>
 #include <linux/module.h>
 #include <linux/of.h>
 

drivers/gpu/drm/drm_panel_backlight_quirks.c

@@ -2,6 +2,7 @@
 
 #include <linux/array_size.h>
 #include <linux/dmi.h>
+#include <linux/export.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <drm/drm_edid.h>

drivers/gpu/drm/drm_panel_orientation_quirks.c

@@ -9,6 +9,7 @@
  */
 
 #include <linux/dmi.h>
+#include <linux/export.h>
 #include <linux/module.h>
 #include <drm/drm_connector.h>
 #include <drm/drm_utils.h>

drivers/gpu/drm/panel/panel-samsung-s6e63m0.c

@@ -13,6 +13,7 @@
 
 #include <linux/backlight.h>
 #include <linux/delay.h>
+#include <linux/export.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/property.h>