arm: dts: socfpga: use reset-name "stmmaceth-ocp" instead of "ahb"

The ahb reset is deasserted in probe before first register access, while the
stmmacheth-ocp reset needs to be asserted every time before changing the phy
mode in Arria10[1].

Changed in Upstream to "ahb"(331085a4  arm64: dts: socfpga: change the
reset-name of "stmmaceth-ocp" to "ahb" ).This change was intended for arm64
socfpga and it is not applicable to Arria10.

Further with STMMAC-SELFTEST Driver enabled, ethtool test also FAILS.
$ ethtool -t eth0
[  322.946709] socfpga-dwmac ff800000.ethernet eth0: entered promiscuous mode
[  323.374558] socfpga-dwmac ff800000.ethernet eth0: left promiscuous mode
The test result is FAIL
The test extra info:
 1. MAC Loopback                 0
 2. PHY Loopback                 -110
 3. MMC Counters                 -110
 4. EEE                          -95
 5. Hash Filter MC               0
 6. Perfect Filter UC            -110
 7. MC Filter                    -110
 8. UC Filter                    0
 9. Flow Control                 -110
10. RSS                          -95
11. VLAN Filtering               -95
12. VLAN Filtering (perf)        -95
13. Double VLAN Filter           -95
14. Double VLAN Filter (perf)    -95
15. Flexible RX Parser           -95
16. SA Insertion (desc)          -95
17. SA Replacement (desc)        -95
18. SA Insertion (reg)           -95
19. SA Replacement (reg)         -95
20. VLAN TX Insertion            -95
21. SVLAN TX Insertion           -95
22. L3 DA Filtering              -95
23. L3 SA Filtering              -95
24. L4 DA TCP Filtering          -95
25. L4 SA TCP Filtering          -95
26. L4 DA UDP Filtering          -95
27. L4 SA UDP Filtering          -95
28. ARP Offload                  -95
29. Jumbo Frame                  -110
30. Multichannel Jumbo           -95
31. Split Header                 -95
32. TBS (ETF Scheduler)          -95

[  324.881327] socfpga-dwmac ff800000.ethernet eth0: Link is Down
[  327.995360] socfpga-dwmac ff800000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx

Link:[1] https://www.intel.com/content/www/us/en/docs/programmable/683711/21-2/functional-description-of-the-emac.html


Fixes: 331085a4 ("arm64: dts: socfpga: change the reset-name of "stmmaceth-ocp" to "ahb")
Signed-off-by: Mamta Shukla <mamta.shukla@leica-geosystems.com>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>