cc/gcc: fix building core when building statically

There was a mishap when cut-n-pasting code from the final
step into the core step: a variable was not renamed.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
(transplanted from 811cf89e81618fb6994c016dd3467072411da2d5)

 reporter_name="Remy Bohmer"

 reporter_url="linux@bohmer.net"

 reporter_comment="Example for building a toolchain for m68000 bare metal targets"