Rename asprintf to _asprintf to avoid unused-result warnings

[Leixb]

Changes made

fixes #335

It would probably be best to actually check the return values for errors on writing. Maybe somethign along these lines:

#define ASSERT_ASPRINTF(x) { if (x < 0) {fprintf(stderr, "Error formatting output"); }

Checklist

• I adjusted the README (if needed)
• For new features in HeadsetControl: I discussed it beforehand in Issues or Discussions and adhered to the wiki