babblesim: Remove sbrk

We do not need it since this works natively with libc.

babblesim/hw/bsp/nrf52_bsim/src/sbrk.c

@@ -1,59 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *  http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-#include <hal/hal_bsp.h>
-
-/* put these in the data section so they are not cleared by _start */
-static char *sbrkBase __attribute__ ((section (".data")));
-static char *sbrkLimit __attribute__ ((section (".data")));
-static char *brk __attribute__ ((section (".data")));
-
-void
-_sbrkInit(char *base, char *limit) {
-    sbrkBase = base;
-    sbrkLimit = limit;
-    brk = base;
-}
-
-void *
-_sbrk(int incr)
-{
-    void *prev_brk;
-
-    if (incr < 0) {
-        /* Returning memory to the heap. */
-        incr = -incr;
-        if (brk - incr < sbrkBase) {
-            prev_brk = (void *)-1;
-        } else {
-            prev_brk = brk;
-            brk -= incr;
-        }
-    } else {
-        /* Allocating memory from the heap. */
-        if (sbrkLimit - brk >= incr) {
-            prev_brk = brk;
-            brk += incr;
-        } else {
-            prev_brk = (void *)-1;
-        }
-    }
-
-    return prev_brk;
-}

babblesim/hw/bsp/nrf52_bsim/syscfg.yml

@@ -34,6 +34,7 @@ syscfg.defs:
         value: 0
 
 syscfg.vals:
+    HAL_SBRK: 0
     OS_MAIN_STACK_SIZE: 8000
     MCU_TIMER_POLLER_PRIO: 0
     BLE_LL_PRIO: 1