Add comment to `std::os::unix::ffi::os_str` explaining that the module is reused on other platforms.
Add comment to `std::os::unix::ffi::os_str` explaining that the module is reused on other platforms.

aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust