examples: Drop sysprof_clock_init() call from example

It’s implicitly called when setting up the `SysprofCaptureWriter`.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

examples/app.c

@@ -23,8 +23,6 @@ main (int   argc,
 {
   SysprofCaptureWriter *writer;
 
-  sysprof_clock_init ();
-
   /* Ignore SIGPIPE because we might get a pipe from the environment and we
    * don't want to trap if write() is used on it.
    */