Snippets for gap 4.15.1 from Nix aarch64-darwin

Sourced from https://hydra.nixos.org/log/gj14sh04jzflp4aa9hna6hdfiynazi49-gap-4.15.1.drv.

• src/down_class.c:36:38: warning: comparison of integers of different signs: 'unsigned int' and 'int' [-Wsign-compare]
  

• src/fplsa4.c:4751:9: warning: misleading indentation; statement is not part of the previous 'else' [-Wmisleading-indentation]