v8.1 stable AGNi for MIATOLL excalibur/curtana/joyeuse/gram

net/sched: Implement Common Applications Kept Enhanced (CAKE) packet scheduler from 4.19
Compile using Snapdragon LLVM clang 12.0.2
Merge CAF LA.UM.8.9.r1-11700-SM6xx.0 (MIUI Q/AOSP QR)
qcacld-3.0: Merge wifi CAF LA.UM.8.9.r1-11700-SM6xx.0 (MIUI Q/AOSP QR)
hid: add valve steam & nintendo hid drivers from CAF LA.UM.9.1.r1-08600-SMxxx0.0 (MIUI Q/AOSP QR)
net: update wireguard v1.0.20210219
Merge kernel 4.14.221
fs: implement exfat v5.8.2 - arter97
net: tweak various parameters for more performance + bbr enabled.
kernel/sched: disable sched gentle fair sleepers.
mmc: restore to CAF + Xiaomi gram-oss state.
qcacld-3.0: disable 802.11ax (WIFI 6) support as our wcn9330 chip doesnt support it.
Rebase AOSP R with encryption configuration