pgsql: Use xmlAddChildList not xmlAddChild in XMLSERIALIZE.

Use xmlAddChildList not xmlAddChild in XMLSERIALIZE.

It looks like we should have been doing this all along,
but we got away with the wrong coding until libxml2 2.13.0
tightened up xmlAddChild's behavior.

There is more stuff to be fixed to be compatible with 2.13.0,
and it will all need to be back-patched.  This is just a
trial commit to see if the buildfarm agrees that we can use
xmlAddChildList unconditionally.

Erik Wienhold, per report from Frank Streitzig.

Discussion: https://postgr.es/m/trinity-b0161630-d230-4598-9ebc-7a23acdb37cb-1720186432160@3c-app-gmx-bap25
Discussion: https://postgr.es/m/trinity-361ba18b-541a-4fe7-bc63-655ae3a7d599-1720259822452@3c-app-gmx-bs01

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/066e8ac6ea8bc2af79dc86273a09ba7c1a39f7fd

Modified Files
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src/backend/utils/adt/xml.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)