Wrong types in batched Householder transform

Seen in a complex build:
```
../../runner/_work/Trilinos/Trilinos/packages/kokkos-kernels/batched/dense/impl/KokkosBatched_Householder_TeamVector_Internal.hpp:51:15: error: no match for 'operator+=' (operand types are 'mag_type' {aka 'double'} and 'Kokkos::complex<double>')
   51 |           val += x2_at_i * x2_at_i;
      |           ~~~~^~~~~~~~~~~~~~~~~~~~
```
@lucbv 