doc: fix documentation of enum gd_flags

Correct GD_FLG_CYCLIC_RUNNING documentation to match Sphinx style.

Fixes: d7de5ef62935 ("cyclic: use a flag in gd->flags for recursion protection")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index 02ad8ca..8882912 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -651,7 +651,7 @@
 	 */
 	GD_FLG_FDT_CHANGED = 0x100000,
 	/**
-	 * GD_FLG_CYCLIC_RUNNING: cyclic_run is in progress
+	 * @GD_FLG_CYCLIC_RUNNING: cyclic_run is in progress
 	 */
 	GD_FLG_CYCLIC_RUNNING = 0x200000,
 };