Cannot use word `_offset` in local variable name in inline assembly because of old 0.7.x syntax

## Description

I have the following Solidity code with the inline assembly part that does not compile. See example below.
It always return me the following error:

```
DeclarationError: Identifier not found. Use ".slot" and ".offset" to access storage variables.
--> contracts/Playground.sol:23:24:
|
23 | revert(resultdata_offset, resultdata_size)
| ^^^^^^^^^^^^^^^^^
```


I am wondering if this is normal. As far as I am aware, this is related to the old syntax from v0.7.x, where the suffixes `_slot` and `_offset` were used to access the slot number of a state variable (or its offset position in a storage slot). This was replaced by `.slot` and `.offset`.

https://docs.soliditylang.org/en/v0.8.21/070-breaking-changes.html#inline-assembly


However, in this instance, I am just writing the local variable in assembly in `snake_case` with the word `_offset` and the compiler seems to confuse this with the old syntax. I am not sure if this is a bug or an inaccuracy in the error reported. If the two words `_slot` and `_offset` are not allowed for local variables in inline assembly, it would be useful I guess to mention it somewhere in the docs maybe?

## Environment

- Compiler version: 0.8.21
- Target EVM version (as per compiler settings): default
- Framework/IDE (e.g. Truffle or Remix): Remix

## Steps to Reproduce

```solidity
// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.21;

contract Example {

address someAddress = 0xCAfEcAfeCAfECaFeCaFecaFecaFECafECafeCaFe;

bytes4 private constant _SOME_SELECTOR = bytes4(keccak256("hey()"));

function test() public payable {
(bool success, bytes memory result) = someAddress.call(
abi.encodePacked(_SOME_SELECTOR, msg.sender, msg.value)
);

assembly {
// `mload(result)` -> offset in memory where `result.length` is located
// `add(result, 32)` -> offset in memory where `result` data starts
let resultdata_size := mload(result)
let resultdata_offset := add(result, 32)

// if call failed, revert
if eq(success, 0) {
revert(resultdata_offset, resultdata_size)
}

// otherwise return the data returned by the external call
return(resultdata_offset, resultdata_size)
}
}

}
```

Reproduce the contract from the issue with Solidity 0.8.21 and inspect how inline assembly identifiers containing `_offset` are parsed and diagnosed. Compare the error with the documented 0.7.x-to-0.8.x inline assembly syntax change; done means the behavior is corrected or its restriction and rationale are documented.

Written by the indexing model from the issue text.