cts: Skip CtsInitTestCases over a native bridge.

The set of linked binaries was making it difficult to run
the test over a native bridge. Since init won't usually
run over a native bridge, the test can be skipped.

Bug: 161081809, 142324733, 162288553
Test: Arm build of CtsInitTestCases skips rammus-arc-r Chromebook.
Change-Id: Icdd8b03111d0f3fd6658ee6d9a97fca27181db45
(cherry picked from commit 9cecf842)