[Bug c/65781] gcc-5.1.0-RC-20150412 thinks it is 5.0.1

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65781

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Please see https://gcc.gnu.org/develop.html .

Basically 5.1.0 is the version for the released version 5.0.1 is for
prereleases.