Add an static cast to compare unsigned with unsigned

[Fettpet]

Problem:
The count variable is an unsigned integer. The result of the numeric_limit::max() call is a signed integer. The gcc with -Wall parameter warns about this compare.

Solution:
The result of the numeric_limit::max call is cast to an unsigned value. This prevents that the gcc warns about the compare.

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[Fettpet]

@googlebot I signed it!

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[Fettpet]

@googlebot I fixed it.

[sergiud]

There's a typo in your commit message: "an static [...]".

[sergiud]

Thanks!