pgsql: Reorder two functions in inval.c

Reorder two functions in inval.c

This file separates public and static functions with a separator
comment, but two routines were not defined in a location reflecting
that, so reorder them.

Author: Aleksander Alekseev
Reviewed-by: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/CAJ7c6TMX2dd0g91UKvcC+CVygKQYJkKJq1+ZzT4rOK42+b53=w@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c2bdd2c5b1d48a7e39e1a8d5e1d90b731b53c4c9

Modified Files
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src/backend/utils/cache/inval.c | 183 ++++++++++++++++++++--------------------
1 file changed, 91 insertions(+), 92 deletions(-)