When manipulating flags, |= rather than +=

Test: as follows
    - builds
    - flashes
    - boots
    - runtest -x external/android-clat/clatd_test.cpp passes
Bug: 64133961
Bug: 72345192

Merged-In: I10367d3b83acce55e3492812fd04cbdf5f0e6e1a
Merged-In: I5c13652a2c79c07318cc20311c9666535df91d7d
Change-Id: Ieb46fa6a158ec7470e261cc6e9345a3266c81a04
(cherry picked from commit f1c79f8dac61141a518b87361cfef0619e3ef49e)
1 file changed