Soong: Add synopsis to several modules under cc package.

Added synopsis to the following modules under cc package:
    * cc_binary
    * cc_binary_host
    * cc_defaults
    * cc_genrule
    * cc_test
    * cc_test_host

Bug: b/128337482
Test: Generated the documentation and verified that the
synopsis was added to each of the module.

Change-Id: I23b7eda449c340783d7cc592df5d2bd399255bf9