[sysprof] writer: increment the next counter id, not the return value

[Christian Hergert <chergert src gnome org>]

commit 48420b0c87af72e195cb261e4f6d3b240edde8c7
Author: Christian Hergert <chergert redhat com>
Date:   Fri Apr 15 04:49:02 2016 -0700

    writer: increment the next counter id, not the return value

 lib/sp-capture-writer.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/lib/sp-capture-writer.c b/lib/sp-capture-writer.c
index d96d3cb..4bd8bfd 100644
--- a/lib/sp-capture-writer.c
+++ b/lib/sp-capture-writer.c
@@ -1101,7 +1101,7 @@ sp_capture_writer_request_counter (SpCaptureWriter *self,
   g_assert (self != NULL);
 
   ret = self->next_counter_id;
-  ret += n_counters;
+  self->next_counter_id += n_counters;
 
   return ret;
 }