build failure with libxkbcommon 1.6

[plugwash]

As a result of Debian rebuild tests, It was recently reported that the xkb crate was failing to build in Debian sid. This appears to have been caused by the upgrade of libxkbcommon to 1.6.

error[E0425]: cannot find value XKB_KEY_dead_lowline in this scope --> src/key.rs:273:41	273	pub const dead_lowline: Keysym = Keysym(XKB_KEY_dead_lowline);	^^^^^^^^^^^^^^^^^^^^ help: a constant with a similar name exists: XKB_KEY_dead_belowring --> /usr/share/cargo/registry/xkb-0.3.0/target/x86_64-unknown-linux-gnu/debug/build/xkbcommon-sys-36ae4d965b839a00/out/bindings.rs:3:16536

= note: similarly named constant `XKB_KEY_dead_belowring` defined here

error[E0425]: cannot find value XKB_KEY_dead_aboveverticalline in this scope --> src/key.rs:274:51 | 274 | pub const dead_aboveverticalline: Keysym = Keysym(XKB_KEY_dead_aboveverticalline); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope

error[E0425]: cannot find value XKB_KEY_dead_belowverticalline in this scope --> src/key.rs:275:51	275	pub const dead_belowverticalline: Keysym = Keysym(XKB_KEY_dead_belowverticalline);	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: a constant with a similar name exists: XKB_KEY_dead_belowtilde --> /usr/share/cargo/registry/xkb-0.3.0/target/x86_64-unknown-linux-gnu/debug/build/xkbcommon-sys-36ae4d965b839a00/out/bindings.rs:3:16691

= note: similarly named constant `XKB_KEY_dead_belowtilde` defined here

error[E0425]: cannot find value XKB_KEY_dead_longsolidusoverlay in this scope --> src/key.rs:276:52 | 276 | pub const dead_longsolidusoverlay: Keysym = Keysym(XKB_KEY_dead_longsolidusoverlay); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope

For more information about this error, try rustc --explain E0425. error: could not compile xkb due to 4 previous errors

Doing some searching it appears this was an intentional upstream change.

https://gitlab.freedesktop.org/xorg/proto/xorgproto/-/merge_requests/70/diffs?commit_id=cb44799b72f611eb4c9d7cc185bc3b09e070be08