Use only ARGV after -- in create_rust_makefile

[y-yagi]

I sometimes use Rake with --trace option, but it fails with when loading create_rust_makefile.

$ bundle exec rake --trace
** Invoke default (first_time)
** Invoke test (first_time)
** Invoke compile (first_time)
** Invoke compile:x86_64-linux (first_time)
(omit)
cargo rustc  --manifest-path /home/y-yagi/src/github.com/y-yagi/watchcat/ext/watchcat/Cargo.toml --target-dir /home/y-yagi/src/github.com/y-yagi/watchcat/target --lib --profile release --trace -- -C linker=gcc -L native=/home/y-yagi/.rbenv/versions/3.3.4/lib -L native=/home/linuxbrew/.linuxbrew/opt/gmp/lib -C link-arg=-Wl,-rpath,/home/linuxbrew/.linuxbrew/opt/gmp/lib -C link-arg=-lm -l pthread
error: unexpected argument '--trace' found

  tip: a similar argument exists: '--crate-type'
  tip: to pass '--trace' as a value, use '-- --trace'

Usage: cargo rustc --manifest-path <PATH> --target-dir <DIRECTORY> --lib --profile <PROFILE-NAME> --crate-type <CRATE-TYPE> [ARGS]...

For more information, try '--help'.
make: *** [Makefile:566: /home/y-yagi/src/github.com/y-yagi/watchcat/target/release/libwatchcat.so] エラー 1
rake aborted!

This is because create_rust_makefile always tries to pass ARGV to cargo. To be honest, I'm not sure why create_rust_makefile uses ARGV. But, I think create_rust_makefile only calls via other commands(e.g. Ruby, Rake).
So using ARGV only after -- is commonplace I think.

[ianks]

Good catch, ty