[pallet-revive] change some getter APIs to return value in register (#6920)

Call data, return data and code sizes can never exceed `u32::MAX`; they
are also not generic. Hence we know that they are guaranteed to always
fit into a 64bit register and `revive` can just zero extend them into a
256bit integer value. Which is slightly more efficient than passing them
on the stack.

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Signed-off-by: Cyrill Leutwiler <[email protected]>
Signed-off-by: xermicus <[email protected]>
Co-authored-by: command-bot <>
Co-authored-by: Alexander Theißen <[email protected]>