Bug#925982: pretty useless without local_scan

[Adam Borowski]

Control: severity -1 important

(Justification: exim is nearly completely useless for receiving mails for
an Internet domain -- there's ~100 spams per day per address.)

I've wasted time concurrently coming up with Andreas' findings -- and
indeed, rebuilding with HAVE_LOCAL_SCAN=yes makes spam filtering work again.


Meow!
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⣾⠁⢠⠒⠀⣿⡁ Did ya know that typing "test -j8" instead of "ctest -j8"
⢿⡄⠘⠷⠚⠋⠀ will make your testsuite pass much faster, and fix bugs?
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