cxd56xx: rm sched_[un]lock

According to the current implementation, "cxd56_cpu1siguninit" will only
be called once during the NuttX startup phase,
and it won't involve scenarios of multi-threaded concurrent access.

Signed-off-by: hujun5 <hujun5@xiaomi.com>

arch/arm/src/cxd56xx/cxd56_cpu1signal.c

@@ -169,8 +169,6 @@ int cxd56_cpu1siginit(uint8_t sigtype, void *data)
       return -ENODEV;
     }
 
-  sched_lock();
-
   if (priv->sigtype[sigtype].use)
     {
       ret = -EBUSY;
@@ -188,8 +186,6 @@ int cxd56_cpu1siginit(uint8_t sigtype, void *data)
 
   priv->ndev++;
 
-  sched_unlock();
-
   cxd56_iccinit(CXD56_PROTO_GNSS);
 
   ret = cxd56_iccinitmsg(CXD56CPU1_CPUID);
@@ -221,7 +217,6 @@ err0:
   return ret;
 
 err1:
-  sched_unlock();
   return ret;
 }
 
@@ -236,12 +231,9 @@ int cxd56_cpu1siguninit(uint8_t sigtype)
       return -ENODEV;
     }
 
-  sched_lock();
-
   if (!priv->sigtype[sigtype].use)
     {
       ret = -EBUSY;
-      sched_unlock();
       return ret;
     }
 
@@ -258,8 +250,6 @@ int cxd56_cpu1siguninit(uint8_t sigtype)
   pid             = priv->workerpid;
   priv->workerpid = INVALID_PROCESS_ID;
 
-  sched_unlock();
-
   ret = kthread_delete(pid);
 
   if (ret)