pgsql: libpq: Trace responses to SSLRequest and GSSENCRequest

libpq: Trace responses to SSLRequest and GSSENCRequest

Since these are single bytes instead of v2 or v3 messages they need
custom tracing logic.  These "messages" don't even have official names
in the protocol specification, so I (Jelte) called them SSLResponse and
GSSENCResponse here.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a5c6b8f22c206aaa22fc9a826f858a262a023cd5

Modified Files
--------------
src/interfaces/libpq/fe-connect.c | 14 ++++++++++++++
src/interfaces/libpq/fe-trace.c   | 20 ++++++++++++++++++++
src/interfaces/libpq/libpq-int.h  |  2 ++
3 files changed, 36 insertions(+)