[roll pigweed] pw_polyfill: Build file and docs cleanup

- Remove unnecessary polyfill-related build targets.
- Update the polyfill docs to include all backported features.
- Remove std::span polyfills from the CMake build.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/100403

https://pigweed.googlesource.com/pigweed/pigweed
pigweed Rolled-Commits: 813fb533ab13f77..e9b9ad3bdd98906
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Change-Id: I7e8c729cd187f5c160fa958f1bda767b972ac6b4
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/zephyr-integration/+/100414
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1 file changed
tree: 1446b7bc63afb4f5827b4163d21a2ed699e2d262
  1. .gitmodules
  2. test.sh