drv/bluetooth_stm32_cc2640: retry on bleMemAllocError

Apparently we are starting to run out of RAM on the CC2640 chips and we
are now occasionally getting bleMemAllocError when trying to send
notifications.

This adds bleMemAllocError to the retry test cases. It also adds
handling of cancellation so we can't get stuck in an infinite retry
loop.

Fixes: pybricks/support#736

lib/pbio/drv/bluetooth/bluetooth_stm32_cc2640.c

@@ -406,7 +406,13 @@ static PT_THREAD(send_value_notification(struct pt *pt, pbio_task_t *task))
     PT_WAIT_UNTIL(pt, hci_command_status);
 
     HCI_StatusCodes_t status = read_buf[8];
-    if (status == blePending) {
+
+    if (status == blePending || status == bleMemAllocError) {
+        if (task->cancel) {
+            task->status = PBIO_ERROR_CANCELED;
+            goto done;
+        }
+
         goto retry;
     }
 
@@ -604,7 +610,12 @@ static PT_THREAD(scan_and_connect_task(struct pt *pt, pbio_task_t *task)) {
 
     HCI_StatusCodes_t status = read_buf[8];
 
-    if (status == blePending) {
+    if (status == blePending || status == bleMemAllocError) {
+        if (task->cancel) {
+            task->status = PBIO_ERROR_CANCELED;
+            goto disconnect;
+        }
+
         goto retry;
     }
 
@@ -667,11 +678,11 @@ static PT_THREAD(write_remote_task(struct pt *pt, pbio_task_t *task)) {
     HCI_StatusCodes_t status = read_buf[8];
 
     if (status != bleSUCCESS) {
-        if (task->cancel) {
-            goto cancel;
-        }
+        if (status == blePending || status == bleMemAllocError) {
+            if (task->cancel) {
+                goto cancel;
+            }
 
-        if (status == blePending) {
             goto retry;
         }