Add sap deployment target check

[ismirlia]

Require system-type to be set if deployment-target is set.

JIRA: https://jsw.ibm.com/browse/POWERIAAS-17001

EDIT:

2024-12-17T04:41:58.030-0600 [ERROR] vertex "ibm_pi_instance.example" error: Missing required argument
╷
│ Error: Missing required argument
│ 
│   with ibm_pi_instance.example,
│   on main.tf line 77, in resource "ibm_pi_instance" "example":
│   77: resource "ibm_pi_instance" "example" {
│ 
│ "pi_deployment_target": all of `pi_deployment_target,pi_sys_type` must be specified
╵
2024-12-17T04:41:58.033-0600 [DEBUG] provider.stdio: received EOF, stopping recv loop: err="rpc error: code = Unavailable desc = error reading from server: EOF"

[ismirlia]

Opened IBM-Cloud#5980, closing this one