Fix support for the nginx ingress controller.

terraform/modules/cluster/main.tf

@@ -46,12 +46,6 @@ variable "public_ingress" {
 variable "ingress_type" {
   description = "What controller should we use to handle incoming http(s) connections."
   type        = string
-  default     = "gateway"
-
-  validation {
-    condition     = contains(["gateway"], var.ingress_type)
-    error_message = "Currently only \"gateway\" is supported."
-  }
 }
 
 variable "main_k8s_namespace" {