doxygen: fix various typos in commands \param and \returns

Change-Id: If87cec3739449c6a54e24fb2cb81e746d8244da2
diff --git a/src/core/mnl.c b/src/core/mnl.c
index c3f5fe6..d148e1b 100644
--- a/src/core/mnl.c
+++ b/src/core/mnl.c
@@ -54,7 +54,7 @@
 }
 
 /*! create an osmocom-wrapped limnl netlink socket.
- *  \parma[in] ctx talloc context from which to allocate
+ *  \param[in] ctx talloc context from which to allocate
  *  \param[in] bus netlink socket bus ID (see NETLINK_* constants)
  *  \param[in] groups groups of messages to bind/subscribe to
  *  \param[in] mnl_cb callback function called for each incoming message