Staging: comedi: Makefile changes

this patch will sort the 'Comedi USB drivers' section in the
staging/comedi/drivers/Makefile in alphabetical order, and add the
vmk80xx.c driver to the build.

From: Manuel Gebele <forensixs@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>