doxygen: enable AUTOBRIEF, drop \brief

Especially for short descriptions, it is annoying to have to type \brief for
every single API doc.

Drop all \brief and enable the AUTOBRIEF feature of doxygen, which always takes
the first sentence of an API doc as the brief description.

Change-Id: I11a8a821b065a128108641a2a63fb5a2b1916e87
diff --git a/src/write_queue.c b/src/write_queue.c
index 1e4cda5..d929774 100644
--- a/src/write_queue.c
+++ b/src/write_queue.c
@@ -27,12 +27,12 @@
 
 /*! \addtogroup write_queue
  *  @{
- *  \brief write queue for writing \ref msgb to sockets/fd's
+ *  write queue for writing \ref msgb to sockets/fd's
  */
 
 /*! \file write_queue.c */
 
-/*! \brief Select loop function for write queue handling
+/*! Select loop function for write queue handling
  *  \param[in] fd osmocom file descriptor
  *  \param[in] what bit-mask of events that have happened
  *  \returns 0 on success; negative on error
@@ -85,7 +85,7 @@
 	return 0;
 }
 
-/*! \brief Initialize a \ref osmo_wqueue structure
+/*! Initialize a \ref osmo_wqueue structure
  *  \param[in] queue Write queue to operate on
  *  \param[in] max_length Maximum length of write queue
  */
@@ -100,7 +100,7 @@
 	INIT_LLIST_HEAD(&queue->msg_queue);
 }
 
-/*! \brief Enqueue a new \ref msgb into a write queue
+/*! Enqueue a new \ref msgb into a write queue
  *  \param[in] queue Write queue to be used
  *  \param[in] data to-be-enqueued message buffer
  *  \returns 0 on success; negative on error
@@ -120,7 +120,7 @@
 	return 0;
 }
 
-/*! \brief Clear a \ref osmo_wqueue
+/*! Clear a \ref osmo_wqueue
  *  \param[in] queue Write queue to be cleared
  *
  * This function will clear (remove/release) all messages in it.