Fix trivially_copy_pass_by_ref in stable_mir

[practicalrs]

Hi,

This PR fixes the following clippy warnings

warning: this argument (8 byte) is passed by reference, but would be more efficient if passed by value (limit: 8 byte)
    --> compiler/stable_mir/src/mir/body.rs:1042:34
     |
1042 |     fn subslice_ty(ty: Ty, from: &u64, to: &u64, from_end: &bool) -> Result<Ty, Error> {
     |                                  ^^^^ help: consider passing by value instead: `u64`
     |
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref
     = note: requested on the command line with `-W clippy::trivially-copy-pass-by-ref`

warning: this argument (8 byte) is passed by reference, but would be more efficient if passed by value (limit: 8 byte)
    --> compiler/stable_mir/src/mir/body.rs:1042:44
     |
1042 |     fn subslice_ty(ty: Ty, from: &u64, to: &u64, from_end: &bool) -> Result<Ty, Error> {
     |                                            ^^^^ help: consider passing by value instead: `u64`
     |
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref

warning: this argument (1 byte) is passed by reference, but would be more efficient if passed by value (limit: 8 byte)
    --> compiler/stable_mir/src/mir/body.rs:1042:60
     |
1042 |     fn subslice_ty(ty: Ty, from: &u64, to: &u64, from_end: &bool) -> Result<Ty, Error> {
     |                                                            ^^^^^ help: consider passing by value instead: `bool`
     |
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref

Best regards,
Michal

[rustbot]

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[rustbot]

This PR changes Stable MIR

cc @oli-obk, @celinval, @ouz-a

[jieyouxu]

Thanks

[jieyouxu]

@bors r+ rollup

[bors]

📌 Commit 89ea9e4 has been approved by jieyouxu

It is now in the queue for this repository.