`checkImplicitMixed` reports "mixed given" on an array

Bug report

To reproduce (not possible on https://phpstan.org/try cause checkImplicitMixed must be enabled):

<?php declare(strict_types = 1);
$hosts   = [];
$weights = [];
$success = getmxrr('', $hosts, $weights);
echo count($hosts);

PHPStan 1.10.60 is reporting:

Parameter #1 $value of function count expects array|Countable, mixed given.

But the function signature of getmxrr() says it's an array: https://github.com/phpstan/phpstan-src/blob/1.11.x/resources/functionMap.php#L3337

Code snippet that reproduces the problem

No response

Expected output

No error.

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