cuda: disable CUDA plugin for pre-dump

Temporarily disable CUDA plugin for `criu pre-dump`.

pre-dump currently fails with the following error:

Handling VMA with the following smaps entry: 1822c000-18da5000 rw-p 00000000 00:00 0                                  [heap]
Handling VMA with the following smaps entry: 200000000-200200000 ---p 00000000 00:00 0
Handling VMA with the following smaps entry: 200200000-200400000 rw-s 00000000 00:06 895                              /dev/nvidia0
Error (criu/proc_parse.c:116): handle_device_vma plugin failed: No such file or directory
Error (criu/proc_parse.c:632): Can't handle non-regular mapping on 705693's map 200200000
Error (criu/cr-dump.c:1486): Collect mappings (pid: 705693) failed with -1

We plan to enable support for pre-dump by skipping nvidia mappings
in a separate patch.

Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>

plugins/cuda/cuda_plugin.c

@@ -565,6 +565,12 @@ int cuda_plugin_init(int stage)
 {
 	int ret;
 
+	/* Disable CUDA checkpointing with pre-dump */
+	if (stage == CR_PLUGIN_STAGE__PRE_DUMP) {
+		plugin_disabled = true;
+		return 0;
+	}
+
 	if (stage == CR_PLUGIN_STAGE__RESTORE) {
 		if (!check_and_remove_inventory_plugin(CR_PLUGIN_DESC.name, strlen(CR_PLUGIN_DESC.name))) {
 			plugin_disabled = true;