drm: Do not include <linux/export.h>

Fix the compile-time error

drivers/gpu/drm/drm_pci.c: warning: EXPORT_SYMBOL() is not used, but #include <linux/export.h> is present

Signed-off-by: Thomas Zimmermann <[e-mail]>
Fixes: 7d95680d64ac ("scripts/misc-check: check unnecessary #include <linux/export.h> when W=1")
Reviewed-by: André Almeida <[e-mail]>
Cc: Masahiro Yamada <[e-mail]>
Cc: Nathan Chancellor <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/gpu/drm/drm_pci.c

···
  */
 
 #include <linux/dma-mapping.h>
-#include <linux/export.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/pci.h>