crypto: testmgr - add keygen tests for ffdheXYZ(dh) templates

Now that the ffdheXYZ(dh) templates support ephemeral key generation, add
->keygen = 1 TVs for each of them to the testmgr.c.

In order to facilitate string merging by the compiler, set party B's secret
and public keys to the ones specified for party A in the respective
existing known answer test. With GCC 7.5 on x86_64, this leads to an
increase of testmgr.o size by less than half a kB.
Signed-off-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>