Reference to wrong floating point precision in docstring of DSTEMR

[michaelwimmer]

In this line:

https://github.com/Reference-LAPACK/lapack/blob/master/SRC/dsyevr.f#L91

the documentation claims that SSTEIN is called, but in the code DSTEIN is called (as expected)

[langou]

Thanks Michael. Julien.