Reduce the repeated library dependence information

Cmake is generally good at tracking specified dependencies between
libraries.  All that we need to do is to establish a dependency on
OpenSSL's libcrypto for 'gost_core', and then we can reduce the amount
of repeated dependencies for everything that links against 'gost_core'.

(cherry picked from commit 7ca9b827)

# Conflicts:
#	CMakeLists.txt