systems/x11: fix compiler warnings (unitialised variables)

.../systems/x11/primary.c: In function 'dfb_x11_update_screen_handler':
.../systems/x11/primary.c:922:42: warning: 'srces[2]' may be used uninitialized in this function [-Wuninitialized]
.../systems/x11/primary.c:767:10: note: 'srces[2]' was declared here
.../systems/x11/primary.c:922:42: warning: 'pitches[2]' may be used uninitialized in this function [-Wuninitialized]
.../systems/x11/primary.c:768:10: note: 'pitches[2]' was declared here
.../systems/x11/primary.c:922:42: warning: 'srces[1]' may be used uninitialized in this function [-Wuninitialized]
.../systems/x11/primary.c:767:10: note: 'srces[1]' was declared here
.../systems/x11/primary.c:922:42: warning: 'pitches[1]' may be used uninitialized in this function [-Wuninitialized]
.../systems/x11/primary.c:768:10: note: 'pitches[1]' was declared here

Author: andred

systems/x11/primary.c

@@ -764,8 +764,8 @@ static DFBResult
 update_screen( DFBX11 *x11, const DFBRectangle *clip, CoreSurfaceBufferLock *lock, XWindow *xw )
 {
      void                  *dst;
-     u8                    *srces[3];
-     int                    pitches[3];
+     u8                    *srces[3] = { 0 };
+     int                    pitches[3] = { 0 };
      unsigned int           offset = 0;
      XImage                *ximage;
      CoreSurfaceAllocation *allocation;