[C2] [5.4.y] Audio and Mali patch set

[scpcom]

Here are some enhancements to support using C2 (and N1) on kernel 5.4.y:

Odroid C2 Audio
scpcom/linux@4ada22b
scpcom/linux@32687aa
scpcom/linux@738e2f0
scpcom/linux@a8f6fac

Mali 450 Meson Driver (supports both UMP and dumb buffers) and
Mail Midgard and Bifrost Rockchip Driver
scpcom/linux@8f33d39
scpcom/linux@ad94356
scpcom/linux@044e0a5
scpcom/linux@3a3f8ca
scpcom/linux@044f63c
https://github.com/scpcom/linux/commits/sbc-5.4.y/drivers/gpu/arm

I know there is already lima driver for Mali 400/450 and panfrost driver for Mali Bifrost/Midgard in the kernel, but I could not get them to work. The classic drivers above work well and stable on Ubuntu 20.04 with X11/XFCE.

Odroid N1 Initial Support
scpcom/linux@808574a
scpcom/linux@8ecf120
https://github.com/scpcom/linux/commits/sbc-5.4.y/arch/arm64/boot/dts/rockchip/rk3399-odroidn1-linux.dts

ODROID VU7 Plus
scpcom/linux@08958ec
scpcom/linux@8d2058c

Rockchip RK3399 support pll setting by auto from vendor kernel (generates pixel clock for any resolution)
https://github.com/scpcom/linux/commits/5.4.41-2111-sbc/drivers/clk/rockchip
https://github.com/scpcom/linux/commits/5.4.41-2111-sbc/drivers/gpu/drm/rockchip

This seems to be still needed for stability of C2:
scpcom/linux@fd0b31f
scpcom/linux@1540251

Thermal for C2 (works only together with needed patches above):
scpcom/linux@7e9d32c
scpcom/linux@529f834

Enhance cpuinfo:
scpcom/linux@815ccbf
scpcom/linux@f4b398d
scpcom/linux@ecd49d3
scpcom/linux@8cca039
Enhance RK3399 cpuinfo:
scpcom/linux@a88f34e
scpcom/linux@a1d6ef4
scpcom/linux@803e80d
Enhance Meson GX cpuinfo:
scpcom/linux@74d41b4
scpcom/linux@ddf4dc8
scpcom/linux@e7bfce8
scpcom/linux@89e4e99

Maybe not needed:
scpcom/linux@f875a86
scpcom/linux@b1adf3a
scpcom/linux@34f0cad
scpcom/linux@586d9c9
scpcom/linux@a1110d8