[Bug target/95247] Backport the DRIVER_SELF_SPECS implementation of -mdejagnu-cpu= to GCC 9

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95247

Segher Boessenkool <segher at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2020-05-20
           Assignee|unassigned at gcc dot gnu.org      |segher at gcc dot 
gnu.org
             Status|UNCONFIRMED                 |ASSIGNED