[roll] Roll fuchsia [counters][rust] Generate bindgen crate during build

Currently, rustc_bindgen_golden is used in counters to validate that a
checked-in bindgen file matches the output of running bindgen during the
build. To eliminate the need for checked-in bindings files, this change
refactors counters to define separate rustc_bindgen and rustc_library
targets that generate and compile the counters-bindings library crate
directly during the build.

The counters crate is updated to depend on counters-bindings instead of
checking in src/bindings.rs.

Original-Original-Bug: 512840182
Test: fx build //zircon/kernel/lib/counters:counters-rs
Test: fx clippy //zircon/kernel/lib/counters:counters-rs
Original-Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1694814
Original-Original-Revision: cad062d765875745a9a5b326708e358465ce09ec
GitOrigin-RevId: 7a964038f4a5b3052c5f7088a20763dd278ff27d
Change-Id: I7aa292e6c3f6b3734fb49852da0743eea16799b2
Reviewed-on: https://fuchsia-review.googlesource.com/c/integration/+/1695460
Cr-Commit-Position: refs/heads/main@{#196231}