* kernel: bump 5.4 to 5.4.79

* ramips: add mt7620-nand driver for NAND flash

This add the mt7620-nand driver
and enable nand ubifs for subtarget mt7620
Signed-off-by: NChen Minqiang <ptpt52@gmail.com>
Co-authored-by: NChen Minqiang <ptpt52@gmail.com>

[mac80211]
 5b29614 mac80211: another fix for the sta connection monitor
 1ed6eb1 mac80211: backport sched_set_fifo_low
 cba4120 mac80211: add support for specifying a per-device scan list
 e0d482f rt2x00: mt7620: differentiate based on SoC's CHIP_VER

[package]
 amd64-microcode/intel-microcode/linux-firmware: update version

[mac80211]
 ca5ee6e mac80211: Fix potential endless loop
 2c14710 mac80211: add more AQL fixes/improvements
 91fb3ce mac80211: remove an obsolete patch that is no longer doing anything useful
 acf1733 mac80211: add preliminary support for enabling 802.11ax in config
 d717343 mac80211: update encap offload patches to the latest version
 673062f mac80211: allow bigger A-MSDU sizes in VHT, even if HT is limited
 caf7277 mac80211: do not allow bigger VHT MPDUs than the hardware supports
 cd36c0d mac80211: select the first available channel for 5GHz interfaces
 1c6d456 mac80211: fix regression in station connection monitor optimization
 4bd7689 mac80211: update sta connection monitor regression fix

[target]
 Sync: at91, ath25, ath79, lantiq, mediatek, mvebu.

kernel: bump to 4.14.193, 4.19.138, 5.4.59 (#5350)
  431fb8c mac80211: add AQL improvements
  6bdd4c9 mac80211: add missing backports for building with 4.14 kernels
  0106820 mac80211: add missing return code checks in AQL improvements
  e7f7101 mac80211: rework encapsulation offload support

[package]
  base-files: add function for generating random MAC
  dnsmasq: abort dhcp_check on interface state
  boot: sync upstream source code
  ath10k-ct-firmware/mt76/sch_cake: update to latest git HEAD

[script]
  download: add China Mirror Station

[target]
  Sync: arc770, ath79, bcm63xx, kirkwood, lantiq, layerscape,
        mediatek, mvebu, octeon, oxnas, pistachio, uml
  Sync most of the target patches.

Run-compiled-on: ipq40xx (4.19 & 5.4), ramips

* kernel: bump to 4.14.169, 4.19.101

* uboot: update to latest

* mediatek: bump to v4.19

* ath79: switch to wpad

* Revert 'grub2: update to latest'