pgsql: Remove generation of repl_gram.h

Remove generation of repl_gram.h

It was apparently never necessary.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/b6d45222969a82aff0e9f115842c87136d429479

Modified Files
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src/backend/Makefile | 1 -
src/backend/replication/.gitignore | 1 -
src/backend/replication/Makefile | 4 +---
3 files changed, 1 insertions(+), 5 deletions(-)