powerpc: Stop using of_root #131

Job	Run time
kernel (ppc64_defconfig, fedora-38)	1m 40s
kernel (ppc64_defconfig, korg-5.5.0)	38s
kernel (ppc40x_defconfig, fedora-38)	2m 21s
kernel (ppc40x_defconfig, korg-5.5.0)	2m 21s
kernel (mpc885_ads_defconfig, fedora-38)	6m 1s
kernel (mpc885_ads_defconfig, korg-5.5.0)	3m 16s
kernel (ppc64le_guest_defconfig, fedora-38, ppc64le)	1s
kernel (ppc64le_guest_defconfig, korg-5.5.0, ppc64le)	1s
kernel (ppc44x_defconfig, fedora-38, /linux/arch/powerpc/configs/ppc44x-qemu.config)	1m 59s
kernel (ppc44x_defconfig, korg-5.5.0, /linux/arch/powerpc/configs/ppc44x-qemu.config)	1m 8s
kernel (corenet64_smp_defconfig, fedora-38)	6m 2s
kernel (corenet64_smp_defconfig, korg-5.5.0)	6m 2s
kernel (g5_defconfig, fedora-38, /linux/arch/powerpc/configs/g5-qemu.config)	6m 1s
kernel (g5_defconfig, korg-5.5.0, /linux/arch/powerpc/configs/g5-qemu.config)	6m 0s
kernel (pmac32_defconfig, fedora-38, /linux/arch/powerpc/configs/pmac32-qemu.config)	3m 4s
kernel (pmac32_defconfig, korg-5.5.0, /linux/arch/powerpc/configs/pmac32-qemu.config)	2m 38s
kernel (corenet32_smp_defconfig, fedora-38)	6m 3s
boot	0s
	55m 16s

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