Audio looping fix

[veins1]

An incomplete (non)fix for #2228. Handling only WAVs. Logic is the same for other formats but I didn't want to copy-paste, there's probably a better solution. First PR in my life!

[veins1]

Decided to fix other formats by copy-pasting. Maybe it's not too bad. I believe all formats work correctly now. Can't really test short XM and MOD files ( I don't know where to get them), but full songs loops work.

[raysan5]

@veins1 thanks for the review. I tested it with the provided VS2022 project (MSVC compiler) and compilation failed with multiple errors, related to the void * casting while reading the audio data from file, maybe you tested it compiling as C++? what compiler did you use?

I reviewed the lines and when playing there is no stuttering but I can hear some cracks, did you experienced the same issue?

Also note the PR is not following the raylib coding conventions, please, could you review it?

[veins1]

@raysan5 I'm using the MinGW with notepad++ scripts which are included in raylib Windows Installer.
I hear the cracks too. If I set target fps higher than 30, the crackling is reduced and at 40fps it's completely gone. If I lower it to 1, most of the audio is silence. It's a different issue that was present before and doesn't involve looping.
Hopefully following raylib conventions now.

[raysan5]

@veins1 I'm merging this fix as a temporal solution but the full audio system should actually be redesigned, as noted in the related issue.