Comment 13 for bug 1252664

So the reason I decided to check for kernel version instead of CONFIG_UIDGID_STRICT_TYPE_CHECKS was for possible future proofing. If the kernel in the future fragments with yet another config option for kuid_t, they would likely implement another __kuid_val function for that, and the patch would still work. Granted, we aren't guaranteed that something else won't break in a kernel API change, so it probably doesn't matter.