fix(pm_am62lx_low_power_modes): Fix typo in command for disabling USB

Both USB wakeup sources on AM62L need to be disabled to enter RTC Only +
DDR. Fix the typo that would only show how to disable one USB device.

Signed-off-by: Kendall Willis <k-willis@ti.com>

Author: kwillis01

source/linux/Foundational_Components/Power_Management/pm_am62lx_low_power_modes.rst

@@ -35,7 +35,7 @@ sources.
 .. code-block:: console
 
    root@am62lxx-evm:~# echo disabled > /sys/devices/platform/bus@f0000/f900000.dwc3-usb/power/wakeup
-   root@am62lxx-evm:~# echo disabled > /sys/devices/platform/bus@f0000/f900000.dwc3-usb/power/wakeup
+   root@am62lxx-evm:~# echo disabled > /sys/devices/platform/bus@f0000/f910000.dwc3-usb/power/wakeup
 
 Now the SoC can be suspended using the following command.