Adds a dummy spin lock backend implementation for baremetal
configuration.
The provided implementation makes a single attempt to acquire the
lock and asserts if it is unavailable. It does not perform interrupt
masking or disable global interrupts, so this implementation does
not support simultaneous multi-threaded environments including IRQs,
and is only meant to prevent data corruption.
Change-Id: I4d44b2dd5cc6f38be1188a9f480f61c6d042b855
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/30520
Reviewed-by: Ewout van Bekkum <ewout@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>
Pigweed-Auto-Submit: Prashanth Swaminathan <prashanthsw@google.com>
