Disable the udev cache by default.

When running out of NAND the udev cache caused the init
process to hang power resets.

Signed-off-by: Jeff Horn <jhorn@reachtech.com>
Add sleep to uibfs install

We had occasional flash install failures.  The calls to
sleep seem to give the NAND some time to settle
between commands.

Signed-off-by: Jeff Horn <jhorn@reachtech.com>