Fix off-by-one in superb allocation for svd

valgrind reports errors in SVD. There is very little documentation on
the 'superb' argument of *gesvd. Intel MKL documentation states that its
size should be min(m, n) - 2. However, in the MKL examples min(m, n)
- 1 is used:

https://software.intel.com/sites/products/documentation/doclib/mkl_sa/11/mkl_lapack_examples/lapacke_dgesvd_row.c.htm

Changing the size of superb to min(m, n) -1 resolved the memory error in
valgrind.

Author: danieldk

src/lapack_traits/svd.rs

@@ -50,7 +50,7 @@ macro_rules! impl_svd {
                     (FlagSVD::No, 0, Vec::new())
                 };
                 let mut s = vec![Self::Real::zero(); k as usize];
-                let mut superb = vec![Self::Real::zero(); (k - 2) as usize];
+                let mut superb = vec![Self::Real::zero(); (k - 1) as usize];
                 let info = $gesvd(
                     l.lapacke_layout(),
                     ju as u8,