BUG: Workaround SGEMV segfault in Accelerate (maintenance 0.14.x)

Workaround for SGEMV segfault in Accelerate (OSX version 10.9)
Corrects scipy.linalg.blas.sgemv, ARPACK, SuperLU
similar to: 
https://github.com/numpy/numpy/pull/5223
https://github.com/scipy/scipy/pull/4105
Should be `get_sgemv_fix(lapack_opt)` not `get_sgemv_fix('lapack_opt')`