cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)

Commit 34e5a527 ("cpufreq: cpufreq-dt: extend with
platform_data") changed cpufreq_init() to only call
cpumask_setall(policy->cpus) if the platform data indicates that all
CPUs share the same clock. Before, cpufreq_generic_init() did this
unconditionally.

This causes a crash on r8a7791/koelsch when resuming from s2ram:

    Enabling non-boot CPUs ...
    CPU1: Booted secondary processor
    Unable to handle kernel NULL pointer dereference at virtual address 0000003c
    pgd = ee71f980
    [0000003c] *pgd=6eeb6003, *pmd=6e0e9003, *pte=00000000
    Internal error: Oops: a07 [#1] SMP ARM
    Modules linked in:
    CPU: 0 PID: 1397 Comm: s2ram Tainted: G        W      3.18.0-rc2-koelsch-00762-g7eed2a4e61d2d978 #581
    task: ee6b76c0 ti: ee7f0000 task.ti: ee7f0000
    PC is at __cpufreq_add_dev.isra.24+0x24c/0x77c
    LR is at __cpufreq_add_dev.isra.24+0x244/0x77c
    pc : [<c029e084>]    lr : [<c029e07c>]    psr: 60000153
    sp : ee7f1d48  ip : ee7f1d48  fp : ee7f1d84
    r10: c04e8448  r9 : 00000000  r8 : 00000001
    r7 : c054a8c4  r6 : 00000001  r5 : 00000001  r4 : 00000000
    r3 : 00000000  r2 : 00000000  r1 : 20000153  r0 : c054a950
    Flags: nZCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment user
    Control: 30c5307d  Table: 6e71f980  DAC: fffffffd
    Process s2ram (pid: 1397, stack limit = 0xee7f0240)

    ...

    Backtrace:
    [<c029de38>] (__cpufreq_add_dev.isra.24) from [<c029e620>] (cpufreq_cpu_callback+0x6c/0x74)
     r10:eec75240 r9:c04e8448 r8:c04ef3a0 r7:00000001 r6:00000012 r5:00000000
     r4:00000012
    [<c029e5b4>] (cpufreq_cpu_callback) from [<c003f20c>] (notifier_call_chain+0x48/0x70)
     r4:ffffffdd r3:c029e5b4
    [<c003f1c4>] (notifier_call_chain) from [<c003f2cc>] (__raw_notifier_call_chain+0x1c/0x24)
     r8:00000001 r7:00000010 r6:00000000 r5:00000000 r4:00000012 r3:ffffffff
    [<c003f2b0>] (__raw_notifier_call_chain) from [<c0026a00>] (__cpu_notify+0x34/0x50)
    [<c00269cc>] (__cpu_notify) from [<c0026a34>] (cpu_notify+0x18/0x1c)
     r4:00000001
    [<c0026a1c>] (cpu_notify) from [<c0026c44>] (_cpu_up+0x108/0x144)
    [<c0026b3c>] (_cpu_up) from [<c0381c68>] (enable_nonboot_cpus+0x68/0xb8)
     r10:00000000 r9:c04e8ee6 r8:00000000 r7:00000003 r6:c04e8528 r5:c0506248
     r4:00000001
    [<c0381c00>] (enable_nonboot_cpus) from [<c0059038>] (suspend_devices_and_enter+0x29c/0x3e8)
     r6:c0506e70 r5:00000000 r4:00000000 r3:60000153

Restore the old default of calling cpumask_setall(policy->cpus) if no
platform data is available to fix this.

Fixes: 34e5a527 (cpufreq: cpufreq-dt: extend with platform_data)
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>