ice: fix signed vs unsigned comparisons

Fix the remaining signed vs unsigned issues, which appear
when compiling with -Werror=sign-compare.

Many of these are because there is an external interface that is passing
an int to us (which we can't change) but that we (rightfully) store
and compare against as an unsigned in our data structures.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>