Using fixed LPI number for some Device ID

[Dongjiu Geng]

Hi Marc,
   Sorry to disturb you, Currently the LPI number is not fixed for the device. The LPI number is dynamically allocated start from 8092.
For two OS which shares the ITS, One OS needs to configure the device interrupt required by another OS, and the other OS uses a fixed interrupt
ID to respond the interrupt. Therefore, the LPI IRQ number of the device needed be fixed. I want to upstream this feature that allocate fixed
LPI number for the device that is specified through the DTS. do you agree?  Thanks!