usb: ohci-at91: Use dynamic device name for OHCI HCD creation

usb: ohci-at91: Use dynamic device name for OHCI HCD creation

Use the dynamic device name instead of the hardcoded string "at91"
when creating the OHCI host controller driver.
This ensures that the device name is more flexible
and correctly reflects the actual device in the system.
This will be in sync with ehci at91 driver.

Before this patch:

[root@sam9x75eb ~]$ dmesg | grep usb
[    1.464487] usb usb1: Manufacturer: Linux 6.16.0-rc2 ehci_hcd
[    1.470210] usb usb1: SerialNumber: 700000.usb-ehci
[    1.595683] usb usb2: Manufacturer: Linux 6.16.0-rc2 ohci_hcd
[    1.601406] usb usb2: SerialNumber: at91

After this patch:

[root@sam9x75eb ~]$ dmesg | grep usb
[    1.464487] usb usb1: Manufacturer: Linux 6.16.0-rc2 ehci_hcd
[    1.470210] usb usb1: SerialNumber: 700000.usb-ehci
[    1.595683] usb usb2: Manufacturer: Linux 6.16.0-rc2 ohci_hcd
[    1.601406] usb usb2: SerialNumber: 600000.usb-ohci

Signed-off-by: Mihai Sain <mihai.sain@microchip.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20250616061759.3384-2-mihai.sain@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>