Add a symlink to the Android standard rustfmt.toml config file for ease
of use when formatting new commits. Per go/rust_formatter, this is the
recommended approach.
To run the formatter:
rustfmt --config-path rustfmt.toml loader/bpfloader.rs
Bug: 359646531
Test: Manual
Change-Id: I155e7b859bc86124cf448f91c1da232892c75049
Signed-off-by: Neill Kapron <nkapron@google.com>