Allow vkGetInstanceProcAddr to resolve itself with no instance
Fixes #365
diff --git a/loader/gpa_helper.h b/loader/gpa_helper.h
index 832b68c..01dec6f 100644
--- a/loader/gpa_helper.h
+++ b/loader/gpa_helper.h
@@ -229,6 +229,7 @@
if (!strcmp(name, "EnumerateInstanceExtensionProperties")) return vkEnumerateInstanceExtensionProperties;
if (!strcmp(name, "EnumerateInstanceLayerProperties")) return vkEnumerateInstanceLayerProperties;
if (!strcmp(name, "EnumerateInstanceVersion")) return vkEnumerateInstanceVersion;
+ if (!strcmp(name, "GetInstanceProcAddr")) return vkGetInstanceProcAddr;
return NULL;
}