configs: ls1088ardb: Add support for usb boot target

LS1088A-RDB has MMC, SCSI, DHCP as boot targets,
but the USB support was missing.
Add support for USB as Boot_targets_devices.

Signed-off-by: Era Tiwari <era.tiwari@nxp.com>
Signed-off-by: Pramod Kumar <pramod.kumar_1@nxp.com>
[Rebased]
Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>
1 file changed