pgsql: Fix incorrect variable datatype.

Fix incorrect variable datatype.

Since slot_keep_segs indicates the number of WAL segments not LSN,
its datatype should not be XLogRecPtr.

Back-patch to v13 where this issue was added.

Reported-by: Atsushi Torikoshi
Author: Atsushi Torikoshi, tweaked by Fujii Masao
Discussion: https://postgr.es/m/ebd0d674f3e050222238a960cac5251a@oss.nttdata.com

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a2b94693beb1d052f2b4935384dd6f7f47143669

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