Camera: assert no HAL1 in devices launched in P+

Also remove the length check for getCameraIdList as external
camera providers are supposed to report 0 there.

Test: atest VtsHalCameraProviderV2_4Target (on marlin)
Bug: 69473913
Change-Id: I9059a699a6c46a3aac76454e7e8673d2539d0fa1