linux (RPi): update to 5.15.70

[HiassofT]

Runtime tested on RPi3B+ and RPi4

[pretoriano80]

@HiassofT which are the plans for LE11 kernel ,will remain on 5.xx branch or at some point will switch to 6.x ?
Thanks and sorry for asking this here ,but i couldn't find a better place to ask about it .

[HiassofT]

@pretoriano80 my plan is to switch to kernel 6.0 as soon as 6.0 final is released.

Testing with 6.0-rc already looks very good here, only RPi2/3 USB driver is somewhat broken - see raspberrypi/linux#5189

It's easy to workaround the USB issue though (by disabling FIQ) which I may just do in LE builds until the bug is fixed so it doesn't hold up the switch to 6.0

[pretoriano80]

Nice!You already have a test branch which is publicly available ?

[HiassofT]

I just rebased and pushed my changes here: https://github.com/HiassofT/LibreELEC.tv/tree/le11-kernel-6.0

[pretoriano80]

Thank you!Will test om my RPi4.