dnsdist-1.9.x: Backport 14534 - Add warnings about large values passed to setMaxTCPClientThreads

[rgacogne]

Short description

Backport of #14534 to dnsdist-1.9.x

Checklist

I have:

• read the CONTRIBUTING.md document
• compiled this code
• tested this code
• included documentation (including possible behaviour changes)
• documented the code
• added or modified regression test(s)
• added or modified unit test(s)
• checked that this code was merged to master

[coveralls]

Pull Request Test Coverage Report for Build 10775298575

Details

• 3 of 5 (60.0%) changed or added relevant lines in 1 file are covered.
• 4207 unchanged lines in 84 files lost coverage.
• Overall coverage decreased (-0.02%) to 55.775%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pdns/dnsdist.cc	3	5	60.0%

Files with Coverage Reduction	New Missed Lines	%
pdns/qtype.hh	1	50.0%
pdns/dnsdistdist/test-dnsdisttcp_cc.cc	1	94.97%
pdns/epollmplexer.cc	2	77.71%
pdns/libssl.hh	2	0.0%
pdns/dnsdist-lua-bindings-dnsquestion.cc	2	36.0%
pdns/burtle.hh	2	96.32%
pdns/dnsdistdist/dnsdist-lua-bindings-kvs.cc	2	26.0%
pdns/views.hh	2	42.11%
pdns/dnscrypt.hh	2	33.33%
pdns/pollmplexer.cc	2	82.39%

Totals
Change from base Build 9987810845:	-0.02%
Covered Lines:	47996
Relevant Lines:	65513

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💛 - Coveralls