pgsql: Fix type confusion in AddRelsyncInvalidationMessage

Fix type confusion in AddRelsyncInvalidationMessage

Since this is trying to add a SharedInvalRelSyncMsg rather than
a SharedInvalRelcacheMsg, it should use rs rather than rc.

This makes no difference as things stand, because the two structure
definitions are identical (except for the capitalization of "relid"),
but it's still a good idea to fix it.

Co-authored-by: Stolpovskikh Danil <d(dot)stolpovskikh(at)ftdata(dot)ru>
Co-authored-by: Robert Haas <rhaas(at)postgresql(dot)org>
Discussion: http://postgr.es/m/bd6a5735b72b4afe99af49c3c62901d6@localhost.localdomain

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/99db753c656946bfd1d4ddd3978ebfcee6fb86c0

Modified Files
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src/backend/utils/cache/inval.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)