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/include/osmocom/core/statistics.h b/include/osmocom/core/statistics.h
index 41716cc..5ebb5fc 100644
--- a/include/osmocom/core/statistics.h
+++ b/include/osmocom/core/statistics.h
@@ -1,60 +1,60 @@
 #pragma once
 
 /*! \file statistics.h
- *  \brief Common routines regarding statistics */
+ *  Common routines regarding statistics */
 
 /*! structure representing a single counter */
 struct osmo_counter {
-	struct llist_head list;		/*!< \brief internal list head */
-	const char *name;		/*!< \brief human-readable name */
-	const char *description;	/*!< \brief humn-readable description */
-	unsigned long value;		/*!< \brief current value */
-	unsigned long previous;		/*!< \brief previous value */
+	struct llist_head list;		/*!< internal list head */
+	const char *name;		/*!< human-readable name */
+	const char *description;	/*!< humn-readable description */
+	unsigned long value;		/*!< current value */
+	unsigned long previous;		/*!< previous value */
 };
 
-/*! \brief Decrement counter */
+/*! Decrement counter */
 static inline void osmo_counter_dec(struct osmo_counter *ctr)
 {
 	ctr->value--;
 }
 
-/*! \brief Increment counter */
+/*! Increment counter */
 static inline void osmo_counter_inc(struct osmo_counter *ctr)
 {
 	ctr->value++;
 }
 
-/*! \brief Get current value of counter */
+/*! Get current value of counter */
 static inline unsigned long osmo_counter_get(struct osmo_counter *ctr)
 {
 	return ctr->value;
 }
 
-/*! \brief Reset current value of counter to 0 */
+/*! Reset current value of counter to 0 */
 static inline void osmo_counter_reset(struct osmo_counter *ctr)
 {
 	ctr->value = 0;
 }
 
-/*! \brief Allocate a new counter */
+/*! Allocate a new counter */
 struct osmo_counter *osmo_counter_alloc(const char *name);
 
-/*! \brief Free the specified counter
+/*! Free the specified counter
  *  \param[in] ctr Counter
  */
 void osmo_counter_free(struct osmo_counter *ctr);
 
-/*! \brief Iterate over all counters
+/*! Iterate over all counters
  *  \param[in] handle_counter Call-back function, aborts if rc < 0
  *  \param[in] data Private dtata handed through to \a handle_counter
  */
 int osmo_counters_for_each(int (*handle_counter)(struct osmo_counter *, void *), void *data);
 
-/*! \brief Resolve counter by human-readable name
+/*! Resolve counter by human-readable name
  *  \param[in] name human-readable name of counter
  *  \returns pointer to counter (\ref osmo_counter) or NULL otherwise
  */
 struct osmo_counter *osmo_counter_get_by_name(const char *name);
 
-/*! \brief Return the counter difference since the last call to this function */
+/*! Return the counter difference since the last call to this function */
 int osmo_counter_difference(struct osmo_counter *ctr);