sepolicy: Fix references to self:capability

commit 9b2e0cbe added a new
self:global_capability_class_set macro that covers both self:capability
and self:cap_userns.  Apply the new macro to various self:capability
references that have cropped up since then.

Bug: 112307595
Test: policy diff shows new rules are all cap_userns
Change-Id: I3eb38ef07532a8e693fd549dfdbc4a6df5329609