[tcm-py]: Make tcm_fileio.py aware of udev_path
[tcm-py]: Make tcm_fileio.py aware of udev_path

This patch updates tcm_fileio.py:fd_createvirtdev() to extract the passed fd_dev_name=
parameter and sets /sys/kernel/config/target/core/$FILEIO_HBA/$FILEIO_DEV/udev_path when
said parameter contains a '/dev/' udev path pointing to a underyling struct block_device
to be used with TCM/FILEIO operations.

This patch also updates fd_get_params() to return fd_dev_size=0 when the udev_path is set
for a struct block_device, for which the TCM object size will be determined in kernel space.

Signed-off-by: Nicholas A. Bellinger <978acd1567d5598152161fdf8bf3ca568f950c9b@linux-iscsi.org>

Datera/lio-utils,Datera/lio-utils,Datera/lio-utils,Datera/lio-utils