Pull RT enablement from Thomas Gleixner:
 "Enable PREEMPT_RT on supported architectures:

  After twenty years of development we finally reached the point to
  enable PREEMPT_RT support in the mainline kernel.

  All prerequisites are merged, so enable it on the supported
  architectures ARM64, RISCV and X86(32/64-bit)"

* tag 'sched-rt-2024-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  riscv: Allow to enable PREEMPT_RT.
  arm64: Allow to enable PREEMPT_RT.
  x86: Allow to enable PREEMPT_RT.