ssl: Handle signature_algorithm field in digitally_signed properly
with proper defaults

Added ssl_ECC_SUITE
ssl: Skip second length indicator in EC extensions

We have no need to care about the value of this length indicator so
we do not need to match it or verify it, it is unnecessary work.
Merge remote-tracking branch 'upstream/maint'
ssl: Do not advertise support for algorithms not supported by crypto
Merge remote-tracking branch 'upstream/maint'