libsnapshot_test: Fix loading both the static and dynamic libcrypto libs

libsnapshot_test was depending both directly on libcrypto_static and
indirectly through liblp on libcrypto.  This was causing a failure at
runtime on the sanity check when loading the libcrypto library.
Dropped the dependency on libcrypto_static and switched to the dynamic
libcrypto to fix this violation.

Test: libsnapshot_test
Fixes: 143094706
Change-Id: Iba959e234348f7deb81893c9105a13628ce0eb6e
Signed-off-by: Tobias Thierer <tobiast@google.com>
Signed-off-by: Alessio Balsini <balsini@google.com>