Misc storage exception class name style

All the misc storage exception class name should
be prefixed with "Misc"

Change-Id: I2f6f279d13b92bbb8f573a0d772d7504860bbbe3
Signed-off-by: Shu Ming <shuming@linux.vnet.ibm.com>
Reviewed-on: http://gerrit.ovirt.org/8847
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Adam Litke <alitke@redhat.com>
Reviewed-by: Adam Litke <alitke@redhat.com>