decompress cleanups

[folkertdev]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 95.34884% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
libbz2-rs-sys/src/decompress.rs	95.23%	2 Missing ⚠️

Files with missing lines	Coverage Δ
libbz2-rs-sys/src/bzlib.rs	92.62% <100.00%> (ø)
libbz2-rs-sys/src/decompress.rs	94.15% <95.23%> (+0.52%)	⬆️