Add management mode to CDI spec generation API

These changes add support for generating a management spec to the nvcdi API.
A management spec consists of a single CDI device (`all`) which includes all expected
NVIDIA device nodes, driver libraries, binaries, and IPC sockets.

Signed-off-by: Evan Lezar <elezar@nvidia.com>

pkg/nvcdi/lib.go

@@ -73,6 +73,11 @@ func New(opts ...Option) Interface {
 
 	var lib Interface
 	switch l.resolveMode() {
+	case ModeManagement:
+		if l.vendor == "" {
+			l.vendor = "management.nvidia.com"
+		}
+		lib = (*managementlib)(l)
 	case ModeNvml:
 		if l.nvmllib == nil {
 			l.nvmllib = nvml.New()