Avoid rshim1 on DPU-BMC

Traditionally rshim driver maintains the USB device name so after
USB hotplug it could come back with the same rshim id. There's a
recent change in DPU-BMC to support both UHCI and EHCI drivers
and sometimes both driver are used for the rshim USB, resulting
rshim1 showing up in DPU-BMC Linux which causes functionality
issues with other components. This commit has a change to release
the name when running on 32-bit arm platform to avoid such
problem.

RM #4829848

Author: lsun100

src/rshim.c

@@ -2773,6 +2773,15 @@ void rshim_deregister(rshim_backend_t *bd)
   rshim_fifo_free(bd);
 
   rshim_devs[bd->index] = NULL;
+
+#ifdef __arm__
+  // Clear the device name to allow index reuse on BMC.
+  if ((bd->type == RSH_BACKEND_USB) && rshim_dev_names[bd->index]) {
+    free(rshim_dev_names[bd->index]);
+    rshim_dev_names[bd->index] = NULL;
+  }
+#endif
+
   bd->registered = 0;
 }