package/qemu: bump version to 6.0.0

Other changes:
  - Drop patch 0003-hw-usb-host-libusb.c-fix-build-with-kernel-5.0.patch as it
    is part of 6.0.0.
  - Rename 0004-meson-add-tests-option.patch to
    0003-meson-add-tests-option.patch and refresh it for 6.0.0

Signed-off-by: Adam Duskett <aduskett@rivian.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>