Обсуждение: pgsql: Harden be-gssapi-common.h for headerscheck

Harden be-gssapi-common.h for headerscheck

Surround the contents with a test that the feature is enabled by
configure, to silence header checking tools on systems without GSSAPI
installed.

Backpatch to 12, where the file appeared.

Discussion: https://postgr.es/m/202111161709.u3pbx5lxdimt@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f744519326e1ce4774d0966f7848601a8327eeaa

Modified Files
--------------
src/include/libpq/be-gssapi-common.h | 4 ++++
1 file changed, 4 insertions(+)