Fix the build if there is no -O in the CFLAGS. To fix it by makes

VIDEO_SYNC_PERIOD constant.

PR:		ports/106571
Reported by:	Gerard Seibert <gerard@seibercom.net>
Reviewed by:	marcus (in IRC, FreeNode/#freebsd-gnome)

audio/jack/files/patch-drivers_dummy_dummy_driver.c

@@ -0,0 +1,15 @@
+--- drivers/dummy/dummy_driver.c.orig	Sun Dec 10 16:31:55 2006
++++ drivers/dummy/dummy_driver.c	Sun Dec 10 16:32:27 2006
+@@ -41,10 +41,11 @@
+ /* this is used for calculate what counts as an xrun */
+ #define PRETEND_BUFFER_SIZE 4096
+ 
++#define VIDEO_SYNC_PERIOD 48000 / 30
++
+ void
+ FakeVideoSync( dummy_driver_t *driver )
+ {
+-        static const int VIDEO_SYNC_PERIOD = 48000 / 30;
+         static int vidCounter = VIDEO_SYNC_PERIOD;
+         
+         int period = driver->period_size;