pgsql: ecpg: check return value of replace_variables()

ecpg: check return value of replace_variables()

The function returns false if it fails to allocate memory, so
make sure to check the return value in callsites.

Author: Aleksander Alekseev <aleksander@tigerdata.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAJ7c6TNPrU8ZxgdfN3PyGY1tzo0bgszx+KkqW0Z7zt3heyC1GQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0d82163958005b2ba56f8c58311888d142fa4509

Modified Files
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src/interfaces/ecpg/ecpglib/prepare.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)