Fix add host device example
Fix add host device example

The example is not right in parameter, and also
one command is same as first one, it should be typo
before, we should use 'rw' as example for that.

Signed-off-by: Kai Qiang Wu(Kennan) <03a9957f0460ce3379f6e452396aa35e108b5af5@cn.ibm.com>

swasd/baleno,swasd/baleno,swasd/baleno