pgsql: Ensure the directory for gram.h is created on win32

Ensure the directory for gram.h is created on win32

Result of bad testing of my last commit.

Branch
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REL8_3_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=e6cc57f1fbbbb3acc19bbb05832cac846903fbec

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