nc-0.9.6 fails to build on loongarch64+musl

[alip]

Thanks for the awesome crate and great work! I am the main author of syd and we've been using nc in our project with great joy. Below is an error we have stumbled upon, thanks to help from Alpine Linux folks on loongarch64+musl.

Reference: https://gitlab.alpinelinux.org/alpine/aports/-/jobs/1885076 Excerpt:

error[E0425]: cannot find value `SA_RESTORER` in the crate root
  --> /home/buildozer/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/nc-0.9.6/src/wrappers/sigaction.rs:14:39
   |
14 |         sa_flags: SA_RESTART | crate::SA_RESTORER,
   |                                       ^^^^^^^^^^^ help: a constant with a similar name exists: `SA_RESTART`
   |
  ::: /home/buildozer/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/nc-0.9.6/src/platform/linux-types/uapi/asm_generic/signal_defs.rs:50:1
   |
50 | pub const SA_RESTART: usize = 0x1000_0000;
   | ------------------------------------------ similarly named constant `SA_RESTART` defined here