RP2040: Remove incorrect assertion (#508)

After the xEventGroupWaitBits in vProtLockInternalSpinUnlockWithWait there was an assertion about
pxYiledSpinLock being NULL, however when xEventGroupWaitBits returns, IRQs have been re-enabled
and so it is no longer safe to assert on the state which is protected by IRQs being disabled.

Co-authored-by: graham sanderson <graham.sanderson@raspeberryi.com>
diff --git a/portable/ThirdParty/GCC/RP2040/port.c b/portable/ThirdParty/GCC/RP2040/port.c
index bf6ff15..903ab8a 100644
--- a/portable/ThirdParty/GCC/RP2040/port.c
+++ b/portable/ThirdParty/GCC/RP2040/port.c
@@ -742,9 +742,6 @@
             ulYieldSpinLockSaveValue = ulSave;

             xEventGroupWaitBits( xEventGroup, prvGetEventGroupBit(pxLock->spin_lock),

                                  pdTRUE, pdFALSE, portMAX_DELAY);

-            /* sanity check that interrupts were disabled, then re-enabled during the call, which will have

-             * taken care of the yield */

-            configASSERT( pxYieldSpinLock == NULL);

         }

     }