ocfs2/dlm: remove unnecessary parentheses

Clang warns when more than one set of parentheses is used for a
single conditional statement:

fs/ocfs2/dlm/dlmthread.c:534:18: warning: equality comparison with extraneous
      parentheses [-Wparentheses-equality]
        if ((res->owner == dlm->node_num)) {
             ~~~~~~~~~~~^~~~~~~~~~~~~~~~
fs/ocfs2/dlm/dlmthread.c:534:18: note: remove extraneous parentheses around the
      comparison to silence this warning
        if ((res->owner == dlm->node_num)) {
            ~           ^               ~

Link: http://lkml.kernel.org/r/20180924181929.6853-1-natechancellor@gmail.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2/dlm/dlmthread.c

@@ -531,7 +531,7 @@ void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
 	assert_spin_locked(&res->spinlock);
 
 	/* don't shuffle secondary queues */
-	if ((res->owner == dlm->node_num)) {
+	if (res->owner == dlm->node_num) {
 		if (res->state & (DLM_LOCK_RES_MIGRATING |
 				  DLM_LOCK_RES_BLOCK_DIRTY))
 		    return;