Revert "load the inflate reader and writer to the stack"

[folkertdev]

This reverts commit c264893.

It turns out that loading the reader and writer to the stack is not beneficial in general:

that jump in runtime for chunk size = 7 is the reverted commit.

Loading to the stack does help, but we need to be more specific when we do it.

[codecov]

Codecov Report

Attention: Patch coverage is 95.72650% with 5 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
zlib-rs/src/inflate.rs	95.72%	5 Missing ⚠️

Files with missing lines	Coverage Δ
zlib-rs/src/inflate.rs	95.31% <95.72%> (-0.13%)	⬇️

... and 39 files with indirect coverage changes