MCU only mode: handler for TISCI_MSG_SYS_RESET should clear current owner from ACL for MAIN cores

During the MCU only mode demo, requirement is to reload firmwares on all MAIN cores after exiting low power mode. To reload firmwares, MCU R5 needs to do TISCI_MSG_PROC_REQUEST.

On a cold boot when the cores are being loaded first time, if A72 is running Linux then kernel will try to attach to the already booted cores (by MCU R5) in IPC-only mode. The attach internally does a TISCI_MSG_PROC_REQUEST. Now in steady state the ownership of all MAIN cores lies with A72 Linux as it has requested for the processors, now when the trigger is made to a low power state a SW reset (TISCI_MSG_SYS_RESET) is issued to the MAIN domain and then PMIC state is changed.

When doing a MAIN domain restart after a trigger is made to a exit the low power state, all MAIN cores need to be reloaded by MCU R5. Now in this process when the MCU R5 tries to request access for the MAIN cores, it will get an error as the access control list for the processor still has A72 as the current owner.

To avoid the above the proc_acl[pidx].current_owner_host_id should be set to HOST_FREE_ID for all pidx in the MAIN domain as a part of the cleanup sequence in the TISCI_MSG_SYS_RESET handler.

Currently to work around the issue we are removing the remoteproc modules on a cold boot from Linux user space. This deinitializes the remotepocs and calls TISCI_MSG_PROC_RELEASE which enables MCU R5 to request for processor on subsequent restart of MAIN domain.