goldfish: goldfish_tty_probe() is not using 'i' any more

The only place where 'i' has been used was a dead code that
got removed by 2a248368 ("goldfish: remove unreachable line
of code"). Remove the last reference to the variable as well.

Fixes: 2a248368 ("goldfish: remove unreachable line of code")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>