Camera: Misc VTS test fixes

This CL fixes two tests:
* `systemCameraTest`: Fix incorrect vector initialization. The test was
  accidentally using the size constructor instead of initialization list
  constructor.
* `processMultiCaptureRequestPreview`: Allow unsupported stream configs.
  The test assumed that all stream combinations from physical cameras
  that back a LogicalMultiCamera were supported. This led to false
  test failures. This CL allows the test to exit early if the HAL
  reports that a stream combination is not supported.

Bug: 222648486
Test: `test VtsAidlHalCameraProvider_TargetTest` pass on failing devices
Change-Id: I009cc2f4b8b94a26b813883cdc1403ae0eb5c477