science/py-scipy: Unbreak build with GCC 10

scipy/sparse/linalg/eigen/arpack/ARPACK/SRC/cnaitr.f:666:35:

383 |             call svout (logfil, 1, rnorm, ndigit,
    |                                   2

......

666 |             call svout (logfil, 2, rtemp, ndigit,
    |                                   1

Error: Rank mismatch between actual argument at (1) and actual argument at (2) (scalar and rank-1)
scipy/sparse/linalg/eigen/arpack/ARPACK/SRC/cnaitr.f:737:39:

383 |             call svout (logfil, 1, rnorm, ndigit,
    |                                   2

......

737 |                 call svout (logfil, 2, rtemp, ndigit,
    |                                       1

Error: Rank mismatch between actual argument at (1) and actual argument at (2) (scalar and rank-1)
gfortran10:f77: scipy/sparse/linalg/eigen/arpack/ARPACK/SRC/dsesrt.f
scipy/sparse/linalg/eigen/arpack/ARPACK/SRC/dsaitr.f:671:35:

369 |             call dvout (logfil, 1, rnorm, ndigit,
    |                                   2

......

671 |             call dvout (logfil, 2, xtemp, ndigit,
    |                                   1

Error: Rank mismatch between actual argument at (1) and actual argument at (2) (scalar and rank-1)
scipy/sparse/linalg/eigen/arpack/ARPACK/SRC/dsaitr.f:743:39:

369 |             call dvout (logfil, 1, rnorm, ndigit,
    |                                   2

......

743 |                 call dvout (logfil, 2, xtemp, ndigit,
    |                                       1

Error: Rank mismatch between actual argument at (1) and actual argument at (2) (scalar and rank-1)

http://package18.nyi.freebsd.org/data/121amd64-default-PR244494/2020-06-10_18h04m44s/logs/errors/py27-scipy-1.2.2_1.log
http://package18.nyi.freebsd.org/data/121amd64-default-PR244494/2020-06-10_18h04m44s/logs/errors/py37-scipy-1.2.2_1.log

A better fix would be to update this port to >= 1.5.1 which should
support GCC 10 out of the box and would allow -std=legacy to be
removed again.

PR: 246700