pgsql: Fix compile failure - Mailing list pgsql-committers

Fix compile failure

REL_11_STABLE's configure does not select C99 mode by default, so using
C99 block initializer broke the build for some compilers.  Revert to C89
in that branch.

Author: Michaël Paquier
Discussion: https://postgr.es/m/20190710070122.GE1031@paquier.xyz

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/2ede93de9e80f0f39276c0afabf1621d21180370

Modified Files
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src/backend/commands/tablecmds.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)