Made .c files compile with a C compiler.

ndb/src/common/portlib/NdbMutex.c:
  Turned into C code.
ndb/src/common/portlib/NdbThread.c:
  Turned into C code.

ndb/src/common/portlib/NdbMutex.c

@@ -23,9 +23,9 @@
 
 NdbMutex* NdbMutex_Create(void)
 {
-  DBUG_ENTER("NdbMutex_Create");
   NdbMutex* pNdbMutex;
   int result;
+  DBUG_ENTER("NdbMutex_Create");
   
   pNdbMutex = (NdbMutex*)NdbMem_Allocate(sizeof(NdbMutex));
   DBUG_PRINT("info",("NdbMem_Allocate 0x%lx",pNdbMutex));
@@ -42,8 +42,8 @@ NdbMutex* NdbMutex_Create(void)
 
 int NdbMutex_Destroy(NdbMutex* p_mutex)
 {
-  DBUG_ENTER("NdbMutex_Destroy");
   int result;
+  DBUG_ENTER("NdbMutex_Destroy");
 
   if (p_mutex == NULL)
     DBUG_RETURN(-1);

ndb/src/common/portlib/NdbThread.c

@@ -71,10 +71,10 @@ struct NdbThread* NdbThread_Create(NDB_THREAD_FUNC *p_thread_func,
 		      const char* p_thread_name,
                       NDB_THREAD_PRIO thread_prio)
 {
-  DBUG_ENTER("NdbThread_Create");
   struct NdbThread* tmpThread;
   int result;
   pthread_attr_t thread_attr;
+  DBUG_ENTER("NdbThread_Create");
 
   (void)thread_prio; /* remove warning for unused parameter */