VTS tests should be static

VTS tests can only depend on NDK shared libraries,
they are pushed and run on older desert version.

In theory the VTS tests should be built against the NDK,
but this is not possible due to all the system dependencies.

Bug: 78871270
Test: compile
Change-Id: I48fbffd0316efc151917071c54aa19e533c615df
Signed-off-by: Kevin Rocard <krocard@google.com>