lang: core: embedded: provisioner: Skip bmc if empty

lang/core/embedded/provisioner/main.mcl

@@ -822,6 +822,7 @@ class base:host($name, $config) {
 		Before => Print["ready"],
 	}
 
+	if "${bmc_uri}" != "" {
 		bmc:power "${bmc_uri}" { # TODO: Name() API is not yet stable
 			#password => "hunter2",
 			insecure_password => true, # XXX: get from uri for now
@@ -830,6 +831,7 @@ class base:host($name, $config) {
 
 			Meta:poll => 60, # required until BMC's support real events!
 		}
+	}
 
 	##$str_true = convert.format_bool(true)
 	##$str_false = convert.format_bool(false)