usb: dwc3: simple: add support for Hikey 970

This binding driver is needed for Hikey 970 to work,
as otherwise a Serror is produced:

    [    1.837458] SError Interrupt on CPU0, code 0xbf000002 -- SError
    [    1.837462] CPU: 0 PID: 74 Comm: kworker/0:1 Not tainted 5.8.0+ #205
    [    1.837463] Hardware name: HiKey970 (DT)
    [    1.837465] Workqueue: events deferred_probe_work_func
    [    1.837467] pstate: 20000005 (nzCv daif -PAN -UAO BTYPE=--)
    [    1.837468] pc : _raw_spin_unlock_irqrestore+0x18/0x50
    [    1.837469] lr : regmap_unlock_spinlock+0x14/0x20
    [    1.837470] sp : ffff8000124dba60
    [    1.837471] x29: ffff8000124dba60 x28: 0000000000000000
    [    1.837474] x27: ffff0001b7e854c8 x26: ffff80001204ea18
    [    1.837476] x25: 0000000000000005 x24: ffff800011f918f8
    [    1.837479] x23: ffff800011fbb588 x22: ffff0001b7e40e00
    [    1.837481] x21: 0000000000000100 x20: 0000000000000000
    [    1.837483] x19: ffff0001b767ec00 x18: 00000000ff10c000
    [    1.837485] x17: 0000000000000002 x16: 0000b0740fdb9950
    [    1.837488] x15: ffff8000116c1198 x14: ffffffffffffffff
    [    1.837490] x13: 0000000000000030 x12: 0101010101010101
    [    1.837493] x11: 0000000000000020 x10: ffff0001bf17d130
    [    1.837495] x9 : 0000000000000000 x8 : ffff0001b6938080
    [    1.837497] x7 : 0000000000000000 x6 : 000000000000003f
    [    1.837500] x5 : 0000000000000000 x4 : 0000000000000000
    [    1.837502] x3 : ffff80001096a880 x2 : 0000000000000000
    [    1.837505] x1 : ffff0001b7e40e00 x0 : 0000000100000001
    [    1.837507] Kernel panic - not syncing: Asynchronous SError Interrupt
    [    1.837509] CPU: 0 PID: 74 Comm: kworker/0:1 Not tainted 5.8.0+ #205
    [    1.837510] Hardware name: HiKey970 (DT)
    [    1.837511] Workqueue: events deferred_probe_work_func
    [    1.837513] Call trace:
    [    1.837514]  dump_backtrace+0x0/0x1e0
    [    1.837515]  show_stack+0x18/0x24
    [    1.837516]  dump_stack+0xc0/0x11c
    [    1.837517]  panic+0x15c/0x324
    [    1.837518]  nmi_panic+0x8c/0x90
    [    1.837519]  arm64_serror_panic+0x78/0x84
    [    1.837520]  do_serror+0x158/0x15c
    [    1.837521]  el1_error+0x84/0x100
    [    1.837522]  _raw_spin_unlock_irqrestore+0x18/0x50
    [    1.837523]  regmap_write+0x58/0x80
    [    1.837524]  hi3660_reset_deassert+0x28/0x34
    [    1.837526]  reset_control_deassert+0x50/0x260
    [    1.837527]  reset_control_deassert+0xf4/0x260
    [    1.837528]  dwc3_probe+0x5dc/0xe6c
    [    1.837529]  platform_drv_probe+0x54/0xb0
    [    1.837530]  really_probe+0xe0/0x490
    [    1.837531]  driver_probe_device+0xf4/0x160
    [    1.837532]  __device_attach_driver+0x8c/0x114
    [    1.837533]  bus_for_each_drv+0x78/0xcc
    [    1.837534]  __device_attach+0x108/0x1a0
    [    1.837535]  device_initial_probe+0x14/0x20
    [    1.837537]  bus_probe_device+0x98/0xa0
    [    1.837538]  deferred_probe_work_func+0x88/0xe0
    [    1.837539]  process_one_work+0x1cc/0x350
    [    1.837540]  worker_thread+0x2c0/0x470
    [    1.837541]  kthread+0x154/0x160
    [    1.837542]  ret_from_fork+0x10/0x30
    [    1.837569] SMP: stopping secondary CPUs
    [    1.837570] Kernel Offset: 0x1d0000 from 0xffff800010000000
    [    1.837571] PHYS_OFFSET: 0x0
    [    1.837572] CPU features: 0x240002,20882004
    [    1.837573] Memory Limit: none
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

drivers/usb/dwc3/dwc3-of-simple.c

@@ -176,6 +176,7 @@ static const struct of_device_id of_dwc3_simple_match[] = {
 	{ .compatible = "cavium,octeon-7130-usb-uctl" },
 	{ .compatible = "sprd,sc9860-dwc3" },
 	{ .compatible = "allwinner,sun50i-h6-dwc3" },
+	{ .compatible = "hisilicon,hi3670-dwc3" },
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);