Syncing documentation vs. -help vs. qemu_options table

Syncing documentation vs. -help vs. qemu_options table

Try to keep documentation about command line switches, -help text and
qemu_options table synchronized.

In true Qemu tradition, an include file is generated from single .hx file
containing all relevant information in one place. The include file is
parsed once for getting the enums, another time for getopt tables and
hird time for help messages. Texi documentation for the options is
generated from the same .hx file.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6884 c046a42c-6fe2-441c-8c8c-71466251a162