Fix building for ios

[m-kuhn]

libproc.h is not available on ios, this brings it through the compiler

[codecov]

Codecov Report

Merging #1718 (5aafb35) into main (19000cd) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1718   +/-   ##
=======================================
  Coverage   66.89%   66.89%           
=======================================
  Files         151      151           
  Lines       20761    20761           
=======================================
  Hits        13889    13889           
  Misses       6872     6872           

Impacted Files	Coverage Δ
src/futils.cpp	87.34% <ø> (ø)

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[kevinbackhouse]

I am not able to test this on iOS, but it doesn't affect any of the other platforms so I think it is fine to merge.