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

Add known answer tests for the ffdhe2048(dh), ffdhe3072(dh), ffdhe4096(dh),
ffdhe6144(dh) and ffdhe8192(dh) templates introduced with the previous
patch to the testmgr. All TVs have been generated with OpenSSL.

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>