powerpc/44x: Make ppc44x_idle_init() static

The 44x/fsp2_defconfig build fails with:

arch/powerpc/platforms/44x/idle.c:30:12: error: no previous prototype for ‘ppc44x_idle_init’ [-Werror=missing-prototypes]
30 | int __init ppc44x_idle_init(void)
| ^~~~~~~~~~~~~~~~

Fix it by making ppc44x_idle_init() static.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231129131919.2528517-4-mpe@ellerman.id.au

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 59 temple place suite 330 boston ma 02111
1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 136 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[POWERPC] 4xx: Add idle wait support for 44x platforms

This changes the cpu_idle loop for 44x platforms to utilize the Wait Enable
feature of the CPU. This helps virtulization solutions know when the guest
Linux kernel is in an idle state.

A command line option called "idle" is also added to allow people to change
the idle loop back to the original variation. This is done by setting
"idle=spin" on the kernel command line.

Signed-off-by: Jerone Young <jyoung5@us.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>