Use the num_complex::Complex32 instead of redeclaring it

It works around mozilla/cbindgen#450.

Author: lu-zero

src/lib.rs

@@ -26,7 +26,7 @@ const EBAND_5MS: [usize; 22] = [
     // 0  200 400 600 800  1k 1.2 1.4 1.6  2k 2.4 2.8 3.2  4k 4.8 5.6 6.8  8k 9.6 12k 15.6 20k*/
     0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 34, 40, 48, 60, 78, 100,
 ];
-type Complex = num_complex::Complex<f32>;
+type Complex = num_complex::Complex32;
 
 pub(crate) fn compute_band_corr(out: &mut [f32], x: &[Complex], p: &[Complex]) {
     for y in out.iter_mut() {