Fix compile error on aarch64/arm architectures (resolves #65)

[jerry73204]

This patch fixes the compile error in issue #65. The compile error was caused by this line.

let mut cu_uuid = CUuuid { bytes: [0i8; 16] };

The CUuuid accepts an [c_char; 16] array, where the type alias c_char depends on architecture. The PR replaces it with bytes: [0usize as c_char; 16].