doc: Fix the Doxygen section endings

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
diff --git a/include/osmocom/gsm/rsl.h b/include/osmocom/gsm/rsl.h
index 712d17b..b8e4157 100644
--- a/include/osmocom/gsm/rsl.h
+++ b/include/osmocom/gsm/rsl.h
@@ -50,6 +50,6 @@
 struct msgb *rsl_rll_simple(uint8_t msg_type, uint8_t chan_nr,
 			    uint8_t link_id, int transparent);
 
-/*! }@ */
+/*! @} */
 
 #endif /* _OSMOCORE_RSL_H */