increase crypto_unittest key sizes to satisfy NSS 3.19.1
NSS version 3.19.1 added minimum key size constraints to avoid the Logjam attack:
> The minimum size of keys that NSS will generate has been raised:
> The minimum modulus size for RSA keys is now 512 bits
> The minimum modulus size for DSA keys is now 1023 bits
> The minimum modulus size for Diffie-Hellman keys is now 1023 bits
https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.19.1_release_notes
https://bugzilla.mozilla.org/show_bug.cgi?id=
1138554
BUG=490240
Review URL: https://codereview.chromium.org/
1148193006
Cr-Commit-Position: refs/heads/master@{#333554}