libcgc: Do not repurpose in-use variable
libcgc: Do not repurpose in-use variable

This can lead to a crash, so let's use the unused variable 'j'
instead.

Signed-off-by: Erik Faye-Lund <2a8ffc07e8f57d80a2934ccc3dd1949354d82b2d@gmail.com>

grate-driver/grate,grate-driver/grate,digetx/grate,digetx/grate