pgsql: Add missing "-I." flag when building pg_bsd_indent.

Add missing "-I." flag when building pg_bsd_indent.

This is evidently not required by most compilers, but buildfarm
member fairywren is unhappy without it. It looks like the meson
infrastructure has this right already.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dccef0f2f8f352de3f601f48b94093995ad839ef

Modified Files
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src/tools/pg_bsd_indent/Makefile | 2 ++
1 file changed, 2 insertions(+)