Fix memory leak in initializing vmem.

Much easier to fix it this way than to figure out why X11 needs to
init it before bitmap_con does.

src/conio/bitmap_con.c

@@ -1935,7 +1935,6 @@ int bitmap_drv_init(void (*drawrect_cb) (struct rectlist *data)
 	pthread_mutex_init(&screenlock, NULL);
 	pthread_mutex_init(&free_rect_lock, NULL);
 	pthread_mutex_lock(&vstatlock);
-	vstat.vmem=NULL;
 	vstat.flags = VIDMODES_FLAG_PALETTE_VMEM;
 	pthread_mutex_lock(&screenlock);
 	for (i = 0; i < sizeof(dac_default)/sizeof(struct dac_colors); i++) {

src/conio/vidmodes.c

@@ -305,7 +305,8 @@ void release_vmem(struct vstat_vmem *vm)
 {
 	if (vm == NULL)
 		return;
-	vm->refcount--;
+	if (vm->refcount)
+		vm->refcount--;
 	if (vm->refcount == 0) {
 		FREE_AND_NULL(vm->vmem);
 		FREE_AND_NULL(vm);

src/syncterm/CHANGES

@@ -12,6 +12,7 @@ Fix focus-follows-mouse behaviour in herbstluftwm
 Fix SAUCE binary capture date
 Add Build Options menu item
 Fix saving non-integer scaling in GDI mode
+Fix static 20k memory leak
 
 Version 1.2rc1
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