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_4_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=ed67b6cc2f64d6ef445377744cb0bf7f866ddeba

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