pgsql: Add "%option warn" to all flex input files that lacked it.

Add "%option warn" to all flex input files that lacked it.

This is recommended in the flex manual, and there seems no good reason
not to use it everywhere.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/2e95f1f002bc3f0504dffa6d9ffed0dc914ecec1

Modified Files
--------------
contrib/cube/cubescan.l             |    1 +
contrib/seg/segscan.l               |    1 +
src/backend/bootstrap/bootscanner.l |    1 +
src/backend/utils/misc/guc-file.l   |    1 +
src/bin/psql/psqlscan.l             |    1 +
src/interfaces/ecpg/preproc/pgc.l   |    1 +
src/test/isolation/specscanner.l    |    5 +++--
7 files changed, 9 insertions(+), 2 deletions(-)