pgsql: Check channel binding flag at end of SCRAM exchange

Check channel binding flag at end of SCRAM exchange

We need to check whether the channel-binding flag encoded in the
client-final-message is the same one sent in the client-first-message.

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/86ab28fbd19a6a0742a7f66e69a595b61eb13d00

Modified Files
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src/backend/libpq/auth-scram.c       | 11 ++++++++---
src/interfaces/libpq/fe-auth-scram.c |  4 ++++
2 files changed, 12 insertions(+), 3 deletions(-)