pgsql: Reset InstallXLogFileSegmentActive after walreceiver self-initia

Reset InstallXLogFileSegmentActive after walreceiver self-initiated exit.

After commit cc2c7d65fc27e877c9f407587b0b92d46cd6dd16 added this flag,
failure to reset it caused assertion failures. In non-assert builds, it
made the system fail to achieve the objectives listed in that commit;
chiefly, we might emit a spurious log message. Back-patch to v15, where
that commit first appeared.

Bharath Rupireddy and Kyotaro Horiguchi. Reviewed by Dilip Kumar,
Nathan Bossart and Michael Paquier. Reported by Dilip Kumar.

Discussion: https://postgr.es/m/CAFiTN-sE3ry=ycMPVtC+Djw4Fd7gbUGVv_qqw6qfzp=JLvqT3g@mail.gmail.com

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e36cbef04bd59f5e2e56a180475d64b0dc06d069

Modified Files
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src/backend/access/transam/xlogrecovery.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)