drm/panfrost: Update create_bo flags comment

Update a comment stating create_bo took no flags, since it now takes a
bit mask of optional flags NOEXEC and HEAP.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220109163704.2564-1-alyssa.rosenzweig@collabora.com

include/uapi/drm/panfrost_drm.h

@@ -84,14 +84,14 @@ struct drm_panfrost_wait_bo {
 	__s64 timeout_ns;	/* absolute */
 };
 
+/* Valid flags to pass to drm_panfrost_create_bo */
 #define PANFROST_BO_NOEXEC	1
 #define PANFROST_BO_HEAP	2
 
 /**
  * struct drm_panfrost_create_bo - ioctl argument for creating Panfrost BOs.
  *
- * There are currently no values for the flags argument, but it may be
- * used in a future extension.
+ * The flags argument is a bit mask of PANFROST_BO_* flags.
  */
 struct drm_panfrost_create_bo {
 	__u32 size;