ice: fix potential infinite loop

The loop counter of a for-loop is a u8 however this is being compared
to an int upper bound and this can lead to an infinite loop if the
upper bound is greater than 255 since the loop counter will wrap back
to zero. Fix this potential issue by making the loop counter an int.

Addresses-Coverity: ("Infinite loop")
Fixes: c7aeb4d1

 ("ice: Disable VFs until reset is completed")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>