opal: fix warning

Fixes #5713

Signed-off-by: Nathan Hjelm <hjelmn@me.com>

opal/mca/btl/ofi/btl_ofi.h

@@ -95,7 +95,7 @@ struct mca_btl_ofi_context_t {
     opal_free_list_t frag_list;
 
     /* for thread locking */
-    volatile int32_t lock;
+    opal_atomic_int32_t lock;
 };
 typedef struct mca_btl_ofi_context_t mca_btl_ofi_context_t;
 

opal/runtime/opal_progress.c

@@ -171,7 +171,7 @@ opal_progress_finalize(void)
 
 static int opal_progress_events(void)
 {
-    static volatile int32_t lock = 0;
+    static opal_atomic_int32_t lock = 0;
     int events = 0;
 
     if( opal_progress_event_flag != 0 && !OPAL_THREAD_SWAP_32(&lock, 1) ) {