Fix type of pointer to _umul128

[mborland]

_umul128 expects a pointer of type unsigned long long* instead of uint64_t*.

[codecov]

Codecov Report

Merging #912 (00ba384) into develop (3d751ad) will not change coverage.
The diff coverage is n/a.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop     #912   +/-   ##
========================================
  Coverage    92.97%   92.97%           
========================================
  Files           85       85           
  Lines         8072     8072           
========================================
  Hits          7505     7505           
  Misses         567      567           

Impacted Files	Coverage Δ
...detail/charconv/detail/fast_float/float_common.hpp	62.19% <ø> (ø)

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[grisumbras]

Thanks for the patch!

[cppalliance-bot]

Benchmark test results. More info at https://benchmark.cppalliance.org/jsonbenchmarks-pullrequests/912/pullrequest.html