Fix Travis CI docs issues

Author: Yossi Levy

platform/DirHandle.h

@@ -105,7 +105,7 @@ class DirHandle : private NonCopyable<DirHandle> {
      *  @returns
      *    0 on success,
      *   -1 on error.
-     *  @deprecated Replaced by `DirHandle::close'
+     *  @deprecated Replaced by `int DirHandle::close()'
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::close")
     virtual int closedir() { return close(); };
@@ -117,7 +117,7 @@ class DirHandle : private NonCopyable<DirHandle> {
      *  A pointer to a dirent structure representing the
      *  directory entry at the current position, or NULL on reaching
      *  end of directory or error.
-     * @deprecated Replaced by `DirHandle::read'
+     * @deprecated Replaced by `ssize_t DirHandle::read(struct dirent *ent)
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::read")
     virtual struct dirent *readdir()
@@ -127,7 +127,7 @@ class DirHandle : private NonCopyable<DirHandle> {
     }
 
     /** Resets the position to the beginning of the directory.
-     * @deprecated Replaced by `DirHandle::rewind'
+     * @deprecated Replaced by `void DirHandle::rewind()'
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::rewind")
     virtual void rewinddir() { rewind(); }
@@ -137,15 +137,15 @@ class DirHandle : private NonCopyable<DirHandle> {
      * @returns
      *   the current position,
      *  -1 on error.
-     * @deprecated Replaced by `DirHandle::tell'
+     * @deprecated Replaced by `off_t DirHandle::tell()'
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::tell")
     virtual off_t telldir() { return tell(); }
 
     /** Sets the position of the DirHandle.
      *
      *  @param location The location to seek to. Must be a value returned by telldir.
-     *  @deprecated Replaced by `DirHandle::seek'
+     *  @deprecated Replaced by `void DirHandle::seek(off_t offset)'
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::seek")
     virtual void seekdir(off_t location) { seek(location); }

platform/FileHandle.h

@@ -146,7 +146,7 @@ class FileHandle : private NonCopyable<FileHandle> {
      *  @returns
      *    new file position on success,
      *    -1 on failure or unsupported
-     *  @deprecated Replaced by `FileHandle::seek'
+     *  @deprecated Replaced by `off_t FileHandle::seek(off_t offset, int whence = SEEK_SET)'
      *
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by FileHandle::seek")
@@ -161,7 +161,7 @@ class FileHandle : private NonCopyable<FileHandle> {
      *  @returns
      *    0 on success or un-needed,
      *   -1 on error
-     *  @deprecated Replaced by `FileHandle::sync'
+     *  @deprecated Replaced by `int FileHandle::sync()'
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by FileHandle::sync")
     virtual int fsync()
@@ -173,7 +173,7 @@ class FileHandle : private NonCopyable<FileHandle> {
      *
      *  @returns
      *   Length of the file
-     *  @deprecated Replaced by `FileHandle::size'
+     *  @deprecated Replaced by `off_t FileHandle::size()'
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by FileHandle::size")
     virtual off_t flen()