On Intel platforms which consist of two Ethernet Controllers such as
TGL-H and ADL-S, a unique MDIO bus id is required for MDIO bus to be
successful registered:

[   13.076133] sysfs: cannot create duplicate filename '/class/mdio_bus/stmmac-1'
[   13.083404] CPU: 8 PID: 1898 Comm: systemd-udevd Tainted: G     U            5.11.0-net-next #106
[   13.092410] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-S ADP-S DRR4 CRB, BIOS ADLIFSI1.R00.1494.B00.2012031421 12/03/2020
[   13.105709] Call Trace:
[   13.108176]  dump_stack+0x64/0x7c
[   13.111553]  sysfs_warn_dup+0x56/0x70
[   13.115273]  sysfs_do_create_link_sd.isra.2+0xbd/0xd0
[   13.120371]  device_add+0x4df/0x840
[   13.123917]  ? complete_all+0x2a/0x40
[   13.127636]  __mdiobus_register+0x98/0x310 [libphy]
[   13.132572]  stmmac_mdio_register+0x1c5/0x3f0 [stmmac]
[   13.137771]  ? stmmac_napi_add+0xa5/0xf0 [stmmac]
[   13.142493]  stmmac_dvr_probe+0x806/0xee0 [stmmac]
[   13.147341]  intel_eth_pci_probe+0x1cb/0x250 [dwmac_intel]
[   13.152884]  pci_device_probe+0xd2/0x150
[   13.156897]  really_probe+0xf7/0x4d0
[   13.160527]  driver_probe_device+0x5d/0x140
[   13.164761]  device_driver_attach+0x4f/0x60
[   13.168996]  __driver_attach+0xa2/0x140
[   13.172891]  ? device_driver_attach+0x60/0x60
[   13.177300]  bus_for_each_dev+0x76/0xc0
[   13.181188]  bus_add_driver+0x189/0x230
[   13.185083]  ? 0xffffffffc0795000
[   13.188446]  driver_register+0x5b/0xf0
[   13.192249]  ? 0xffffffffc0795000
[   13.195577]  do_one_initcall+0x4d/0x210
[   13.199467]  ? kmem_cache_alloc_trace+0x2ff/0x490
[   13.204228]  do_init_module+0x5b/0x21c
[   13.208031]  load_module+0x2a0c/0x2de0
[   13.211838]  ? __do_sys_finit_module+0xb1/0x110
[   13.216420]  __do_sys_finit_module+0xb1/0x110
[   13.220825]  do_syscall_64+0x33/0x40
[   13.224451]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   13.229515] RIP: 0033:0x7fc2b1919ccd
[   13.233113] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 93 31 0c 00 f7 d8 64 89 01 48
[   13.251912] RSP: 002b:00007ffcea2e5b98 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[   13.259527] RAX: ffffffffffffffda RBX: 0000560558920f10 RCX: 00007fc2b1919ccd
[   13.266706] RDX: 0000000000000000 RSI: 00007fc2b1a881e3 RDI: 0000000000000012
[   13.273887] RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000000
[   13.281036] R10: 0000000000000012 R11: 0000000000000246 R12: 00007fc2b1a881e3
[   13.288183] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcea2e5d58
[   13.295389] libphy: mii_bus stmmac-1 failed to register

Fixes: 88af9bd4 ("stmmac: intel: Add ADL-S 1Gbps PCI IDs")
Fixes: 8450e23f ("stmmac: intel: Add PCI IDs for TGL-H platform")
Signed-off-by: Wong Vee Khee <vee.khee.wong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>