[COMMITTERS] pgsql: Use "%option prefix" to set API names in ecpg's lexer.

Use "%option prefix" to set API names in ecpg's lexer.

Back-patch commit 92fb64983 into the pre-9.6 branches.

Without this, ecpg fails to build with the latest version of flex.
It's not unreasonable that people would want to compile our old branches
with recent tools.  Per report from Дилян Палаузов.

Discussion: https://postgr.es/m/d845c1af-e18d-6651-178f-9f08cdf37e10@aegee.org

Branch
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REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/15b3722700ca043494804dfd1fe7556c50d4f9e9

Modified Files
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src/interfaces/ecpg/preproc/descriptor.c | 31 ++++++++-------
src/interfaces/ecpg/preproc/ecpg.addons  | 30 +++++++--------
src/interfaces/ecpg/preproc/ecpg.c       | 40 +++++++++----------
src/interfaces/ecpg/preproc/ecpg.header  | 12 +++---
src/interfaces/ecpg/preproc/ecpg.trailer | 18 ++++-----
src/interfaces/ecpg/preproc/extern.h     | 10 ++---
src/interfaces/ecpg/preproc/output.c     | 66 ++++++++++++++++----------------
src/interfaces/ecpg/preproc/parser.c     | 10 ++---
src/interfaces/ecpg/preproc/pgc.l        | 66 ++++++++++++++------------------
src/interfaces/ecpg/preproc/variable.c   |  2 +-
10 files changed, 140 insertions(+), 145 deletions(-)