pgsql: Check after errors of SPI_execute() in xml.c

Check after errors of SPI_execute() in xml.c

SPI gets used to build a list of relation OIDs for XML object
generation, and one code path building a list uses SPI_execute() without
looking at errors it produces.  So fix that.

Author: Mark Dilger
Reviewed-by: Michael Paquier, Pavel Stehule
Discussion: https://postgr.es/m/17d30445-4862-7917-170f-84328dcd292d@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3feb6ace7cfe8edbf6db702de06dc9295f307a8e

Modified Files
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src/backend/utils/adt/xml.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)