FRAME: Unity Balance Conversion for Different IDs of Native Asset (#3659)

Introduce types to define 1:1 balance conversion for different relative
asset ids/locations of native asset.

Examples:
native asset on Asset Hub presented as `VersionedLocatableAsset` type in
the context of Relay Chain is
```
{
  `location`: (0, Parachain(1000)),
  `asset_id`: (1, Here),
}
```
and it's balance should be converted 1:1 by implementations of
`ConversionToAssetBalance` trait.

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Co-authored-by: Branislav Kontur <[email protected]>