kernel: bump 6.6 to 6.6.39

kernel: bump 6.6 to 6.6.39

Changelog: https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.39

Manually rebased:
	generic/backport-6.6/0080-v6.9-smp-Avoid-setup_max_cpus_namespace_collision_shadowing.patch

Removed upstreamed:
	generic/backport-6.6/801-v6.11-gpio-mmio-do-not-calculate-bgpio_bits-via-ngpios.patch[1]
	generic/backport-6.6/0081-v6.10-cpu-Fix-broken-cmdline-nosmp-and-maxcpus-0.patch[2]

All other patches automatically rebased.

1. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v6.6.39&id=dee87316b5f5f167a201491a774bbd6e10c8dd94
2. https://github.com/gregkh/linux/commit/69787793e7f0673465c89714d1522fde978bbfa8

Build system: x86/64
Build-tested: x86/64/AMD Cezanne, flogic/glinet_gl-mt6000, flogic/xiaomi_redmi-router-ax6000-ubootmod, ramips/tplink_archer-a6-v3
Run-tested: x86/64/AMD Cezanne, flogic/glinet_gl-mt6000, flogic/xiaomi_redmi-router-ax6000-ubootmod, ramips/tplink_archer-a6-v3

Signed-off-by: John Audia <therealgraysky@proton.me>
Co-authored-by: Hauke Mehrtens <hauke@hauke-m.de>
Link: https://github.com/openwrt/openwrt/pull/15928
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>