usb: Update Usb and UsbGadget i2c logic

Update the logic to find the i2c bus number to use either the named i2c
devices or the static i2c bus numbers. This allows us to support both
cases -- v5.10 uses i2c-<devname> while v6.1 uses <i2c-bus#>-<reg>.

Bug: 291606723
Test: verify no errors from the usb services with v5.10 and v6.1
Change-Id: Ia68c424a3b6579457be6cfd0d07788e9da44a86e
4 files changed