Doc: Add \a commands to FileSystemWatcher and stringutils docs

Change-Id: Ie76e2d7387df630a512413bd214461979ad2ec91
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/libs/utils/filesystemwatcher.cpp

@@ -188,7 +188,7 @@ void FileSystemWatcherPrivate::autoReloadPostponed(bool postponed)
 }
 
 /*!
-    Adds directories to watcher 0.
+    Creates a file system watcher with the ID 0 and the owner \a parent.
 */
 
 FileSystemWatcher::FileSystemWatcher(QObject *parent) :
@@ -198,7 +198,7 @@ FileSystemWatcher::FileSystemWatcher(QObject *parent) :
 }
 
 /*!
-    Adds directories to a watcher with the specified \a id.
+    Creates a file system watcher with the ID \a id and the owner \a parent.
 */
 
 FileSystemWatcher::FileSystemWatcher(int id, QObject *parent) :

src/libs/utils/stringutils.cpp

@@ -458,7 +458,7 @@ QTCREATOR_UTILS_EXPORT QString normalizeNewlines(const QString &text)
 
 /*!
     Joins all the not empty string list's \a strings into a single string with each element
-    separated by the given separator (which can be an empty string).
+    separated by the given \a separator (which can be an empty string).
 */
 QTCREATOR_UTILS_EXPORT QString joinStrings(const QStringList &strings, QChar separator)
 {