ALSA: ctxfi - Simple code clean up

- replace NULL == xxx with !xxx
- replace NULL != xxx with xxx
- similar trivial cleanups

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/ctxfi/ctresource.c b/sound/pci/ctxfi/ctresource.c
index 889c495..7dfaf67 100644
--- a/sound/pci/ctxfi/ctresource.c
+++ b/sound/pci/ctxfi/ctresource.c
@@ -144,7 +144,7 @@
 	rsc->msr = msr;
 	rsc->hw = hw;
 	rsc->ops = &rsc_generic_ops;
-	if (NULL == hw) {
+	if (!hw) {
 		rsc->ctrl_blk = NULL;
 		return 0;
 	}
@@ -216,7 +216,7 @@
 	mgr->type = NUM_RSCTYP;
 
 	mgr->rscs = kzalloc(((amount + 8 - 1) / 8), GFP_KERNEL);
-	if (NULL == mgr->rscs)
+	if (!mgr->rscs)
 		return -ENOMEM;
 
 	switch (type) {