[mutter] cogl-trace: Include cogl-trace.h even when not tracing

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit d7d75dd8e757351bdcc57fa878a353019b62a742
Author: Daniel van Vugt <daniel van vugt canonical com>
Date:   Wed Jun 26 11:03:46 2019 +0800

    cogl-trace: Include cogl-trace.h even when not tracing
    
    Public functions in C should be declared before they are defined, and
    often compilers warn you if you haven't:
    
    ```
    ../cogl/cogl/cogl-trace.c:237:1: warning: no previous prototype for
    ‘cogl_set_tracing_enabled_on_thread_with_fd’ [-Wmissing-prototypes]
     cogl_set_tracing_enabled_on_thread_with_fd (void       *data,
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../cogl/cogl/cogl-trace.c:245:1: warning: no previous prototype for
    ‘cogl_set_tracing_enabled_on_thread’ [-Wmissing-prototypes]
     cogl_set_tracing_enabled_on_thread (void       *data,
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../cogl/cogl/cogl-trace.c:253:1: warning: no previous prototype for
    ‘cogl_set_tracing_disabled_on_thread’ [-Wmissing-prototypes]
     cogl_set_tracing_disabled_on_thread (void *data)
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ```
    
    In this case the function declarations were not included because
    `HAVE_TRACING` isn't defined. But we should still include `cogl-trace.h`
    because it handles the case of `HAVE_TRACING` not being defined and
    correctly still declares the functions defined in `cogl-trace.c`.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/650

 cogl/cogl/cogl-trace.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/cogl/cogl/cogl-trace.c b/cogl/cogl/cogl-trace.c
index 9e52ec572..983b7d4bb 100644
--- a/cogl/cogl/cogl-trace.c
+++ b/cogl/cogl/cogl-trace.c
@@ -18,10 +18,10 @@
 
 #include "cogl-config.h"
 
-#ifdef HAVE_TRACING
-
 #include "cogl/cogl-trace.h"
 
+#ifdef HAVE_TRACING
+
 #include <sysprof-capture.h>
 #include <syscall.h>
 #include <sys/types.h>