mixing signed and unsigned types in comparison can end up having
unintended results. for example:
if (-1 < 1U)
printf("true\n");
else
printf("false\n");
previously we silenced these warnings, instead just fix them properly
via necessary casting, and in cases where the value cannot be negative
(e.g width/height members) make them unsigned.
Reviewed-on: https://codeberg.org/nsxiv/nsxiv/pulls/336
Reviewed-by: explosion-mental <explosion-mental@noreply.codeberg.org>
c131b1ed83