Fixup target triple name

Author: Digipom

README.md

@@ -111,7 +111,7 @@ Tested:
   * [`i686-apple-darwin`](https://doc.rust-lang.org/libc/i686-apple-darwin/libc/)
   * [`x86_64-apple-darwin`](https://doc.rust-lang.org/libc/x86_64-apple-darwin/libc/)
     (OSX)
-  * `i686-apple-ios`
+  * `i386-apple-ios`
   * `x86_64-apple-ios`
   * [`i686-unknown-linux-gnu`](https://doc.rust-lang.org/libc/i686-unknown-linux-gnu/libc/)
   * [`x86_64-unknown-linux-gnu`](https://doc.rust-lang.org/libc/x86_64-unknown-linux-gnu/libc/)