This commit archives the perl script used to do conversion of the
STEXI/ETEXI blocks in qemu-options.hx. (The other .hx files were
manually converted, but qemu-options.hx is complicated enough that
I felt I needed some scripting.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200228153619.9906-26-peter.maydell@linaro.org