When adding support for parallel subdev for Gen3 it was missed that the
symbol 'i' in rvin_group_link_notify() was already declared, remove the
dupe as it's only used as a loop variable this have no functional
change. This fixes warning:
rcar-core.c:117:52: originally declared here
rcar-core.c:173:30: warning: symbol 'i' shadows an earlier one