[libc++] Expand Android libc++ test config files (#142846)
Parameterize (and rename) existing libc++/libc++abi test configuration
files for the Android NDK to work for both the NDK and platform.
Android LLVM downstream seeks to test libc++ for both the NDK and
platform build (currently only testing the NDK), which will use almost
identical test configuration files. The only difference is the name of
the libc++ shared object used. Because of this we parameterize the
current test files (for both libc++ and libc++abi) with the existing
LIBCXX_SHARED_OUTPUT_NAME cmake variable, and rename the file
accordingly.
