autotools: gtest: Distribute the googletest *.so files

autotools: gtest: Distribute the googletest *.so files

googletest strongly recommends that their library is
rebuilt on each platform, but this runs counter to a
tagged release of code that utilizes gtest.  This commit
enables `make dist` to bundle the googletest *.so files
into the resultant zip file.

Note that these googletest *.so files are dependent upon
a certain version of glibc (and other libraries) and may
not work on distros with very old versions of those
tools.

Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>