pgsql: Free memory allocated for unrecognized_protocol_options

Free memory allocated for unrecognized_protocol_options

Since 4966bd3ed95e Valgrind started to warn about little amount of
memory being leaked in ProcessStartupPacket(). This is not critical
but the warnings may distract from real issues. Fix it by freeing the
list after use.

Author: Aleksander Alekseev <aleksander@tigerdata.com>
Discussion: https://www.postgresql.org/message-id/CAJ7c6TN3Hbb5p=UHx0SPVN+h_JwPAV6rxoqOm7gHBMFKfnGK-Q@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/311a851436cb39145baff61a2936c5d327b040e3

Modified Files
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src/backend/tcop/backend_startup.c | 2 ++
1 file changed, 2 insertions(+)