This consolidates version information, archive's download location,
filename and SHA256 checksum into version.sh. This file is then sourced
from the port script and toolchain build script.
The version.sh script contains the following variables:
- QEMU_VERSION - Version number
- QEMU_ARCHIVE - Filename
- QEMU_ARCHIVE_URL - Full url to download location
- QEMU_ARCHIVE_SHA256SUM - The SHA256 checksum
Use single quotes for non-interpolated strings in the 'configopts' and
'depends' sections.
Let each dependency of the 'depends' section be on a separate line.
