Make HDM RequestorWsPriority values ascending with priority

RequestorWsPriority currently encodes low priority with high int values,
and high priority with low int values. This can lead to confusion when
comparing priority values, thus we should reverse the int values and
have high priority be encoded with high int values, and low priority
encoded with low int values.

Bug: 219530168
Test: atest HalDeviceManagerTest
Change-Id: I983c63ab538bb16dbe5a6e610aff30d69d016cc4
1 file changed