e100.txt: Cleanup license info in kernel doc

Apparently the e100.txt document contained a "License" section left
over from days of old, which does not need to be in the kernel
documentation.  So clean it up..

CC: John Ronciak <john.ronciak@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>