Fix compilation on Windows once more

[skreborn]

Woop-woop! That's the sound of da Windows police!

The pprof crate is unfortunately not compatible with Windows as of now, and thus its inclusion prevents the library from being built even if the relevant code is never accessed. It is only "used" in rumqttd/src/bin.rs, and even then it really isn't, so it is not what you would necessarily call essential.

This change simply gets rid of the offending piece of code and its dependency. Rejoice, for this lets the library be built on Windows once more!

[tekjar]

Instead of removing, can we instead feature gate pprof with !cfg mvsc?

[tekjar]

I thing a profile feature flag also makes sense

[skreborn]

Instead of removing, can we instead feature gate pprof with !cfg mvsc?

That would've been my first approach, but since it was commented out and not doing anything, I've instead opted to remove it completely. If you'd like, I can put it back (either commented or uncommented), but being unable to compile and run the binary with profiling on, I wasn't feeling very confident just uncommenting it, fearing that it might break on a Linux.

Is there a reason it was commented out?

[tekjar]

I think it was commented out by mistake while I was checking throughput difference with and without profiling on

[skreborn]

I've re-added the profiling code for non-Windows targets. I've tested it and it builds and runs successfully on both Windows and Linux - and generates the profiling data successfully on the latter.

[tekjar]

Thanks!! :)