pgsql: Properly install gram.h on MSVC builds

Properly install gram.h on MSVC builds

This file is now needed by pgAdmin builds, which started
failing since it was missing in the installer builds.

Branch
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REL8_3_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=afa5584b25748255a55e665f45c43a72f7f69553

Modified Files
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src/tools/msvc/Install.pm | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)