pgsql: Fix comments in postmaster.c.

Fix comments in postmaster.c.

Commit 86c23a6eb2 changed the option to specify that postgres will
stop all other server processes by sending the signal SIGSTOP,
from -s to -T. But previously there were comments incorrectly
explaining that SIGSTOP behavior is set by -s option. This commit
fixes them.

Author: Kyotaro Horiguchi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/20210316.165141.1400441966284654043.horikyota.ntt@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fd31214075cc740e43edc71ca1c385c8c53047b7

Modified Files
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src/backend/postmaster/postmaster.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)