lowRamDevice TVs can have multi-user

Svelte phones in single-user mode don't pose any problems. TVs in many
regions need multi-user in order to support a restricted profile mode.

Adds a special case for devices with UI_MODE_TYPE_TELEVISION to be able
to enable multi-user (ie. max_users will not be ignored in low_ram cases
as it is on other form factors).

Bug: 71626497
Bug: 67965409
Test: runtest -x frameworks/base/services/tests/servicestests/src/com/android/server/pm/UserManagerTest.java
Change-Id: I6d18b9dca472b9d971d9e51a9d0f4be7403bc26a