examples/vm_power_manager: ensure domain name is null terminated

In add_vm: The string buffer may not have a null terminator if the source
string's length is equal to the buffer size

Coverity issue: 30691
Fixes: e8ae9b662506 ("examples/vm_power: channel manager and monitor in host")

Signed-off-by: Daniel Mrzyglod <danielx.t.mrzyglod@intel.com>

examples/vm_power_manager/channel_manager.c

@@ -667,6 +667,7 @@ add_vm(const char *vm_name)
 		return -1;
 	}
 	strncpy(new_domain->name, vm_name, sizeof(new_domain->name));
+	new_domain->name[sizeof(new_domain->name) - 1] = '\0';
 	new_domain->channel_mask = 0;
 	new_domain->num_channels = 0;