Portenta H7: USB_CORE_ID_HS core only runs as usbhost for ~30s then hangs (KeyboardController)

Running the KeyboardController.ino example, only runs for ~30seconds (sometimes shorter), then hangs when running on the USB-C (HS) core. Sometimes shows the message "RHUB HS:0 Disable 4", sometimes not.

The FS core appears to work fine (USB-A connector requiring a breakout board).

Portenta H7, connected a USB keyboard directly (no-hub) via USB-C -> USB-A adapter, and enabling supplyPowerOnVBUS. Get same results with a hub.

```log
RHUB HS:0 Connect
RHUB HS:0 Enable
DEV HS.00 Allocate pipe, in = 0, out = 1
DEV HS.01 Re-allocate pipe, in = 0, out = 1
DEV HS.01 FS device, VID:046d PID:c52b
ITF HS.01.0-0 HID interface init
ITF HS.01.0-0 Ep in 81
ITF HS.01.1-1 HID interface init
ITF HS.01.1-1 Ep in 82
ITF HS.01.2-2 HID interface init
ITF HS.01.2-2 Ep in 83
DEV HS.01 Device has 3 interfaces
ENDP HS.01.81 Key: 00 00 00 00 00 00 00 00
ENDP HS.01.81 Key: 00 00 00 00 00 00 00 00
ENDP HS.01.81 Key: 00 00 00 00 00 00 00 00
ENDP HS.01.81 Key: 00 00 00 00 00 00 00 00
RHUB HS:0 Disable 4
```

Start with the KeyboardController.ino example on a Portenta H7 using the USB-C HS core and capture the reported log behavior. Compare the HS and FS core runs, focusing on the hang after roughly 30 seconds and the RHUB HS Disable 4 message. Done means the HS core continues operating with the keyboard instead of hanging.

Written by the indexing model from the issue text.