gtest: add license hash

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/gtest/gtest.hash

@@ -1,2 +1,3 @@
 # Locally computed:
 sha256	58a6f4277ca2bc8565222b3bbd58a177609e9c488e8a72649359ba51450db7d8	gtest-release-1.8.0.tar.gz
+sha256	9702de7e4117a8e2b20dafab11ffda58c198aede066406496bef670d40a22138	googletest/LICENSE