Access Provider Instance in Custom Type Semantic Equality Checking

### Use-cases
The semantic equality of an attribute sometimes depend on the state of some other resources on the cloud. Without the access to the cloud provider's Cloud SDK's (e.g. `linodego`) client, it can't determine the semantic equality with only new and old values.

### Proposal
The client of the cloud SDK (not TF SDK) is usually stored in a [provider conifg field](https://github.com/hashicorp/terraform-provider-google/blob/b78417a359449e73d5c9f3bd96b29fc07183c28d/google/fwprovider/framework_provider.go#L40), and it would be nice to have access to the client from the [semantic equality checking function](https://developer.hashicorp.com/terraform/plugin/framework/handling-data/types/custom#semantic-equality).