ALSA: Make snd_BUG_ON() always evaluate and return the conditional expression

Having snd_BUG_ON() only evaluate its conditional when CONFIG_SND_DEBUG
is set leads to frequent bugs, since other similar macros in the kernel
have different behavior. Let's make snd_BUG_ON() act like those macros
so it will stop being accidentally misused.

Signed-off-by: Christine Spang <christine.spang@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/Documentation/DocBook/writing-an-alsa-driver.tmpl b/Documentation/DocBook/writing-an-alsa-driver.tmpl
index bd6fee2..06741e9 100644
--- a/Documentation/DocBook/writing-an-alsa-driver.tmpl
+++ b/Documentation/DocBook/writing-an-alsa-driver.tmpl
@@ -6164,14 +6164,12 @@
 
       <para>
         The macro takes an conditional expression to evaluate.
-	When <constant>CONFIG_SND_DEBUG</constant>, is set, the
-	expression is actually evaluated. If it's non-zero, it shows
-	the warning message such as
+	When <constant>CONFIG_SND_DEBUG</constant>, is set, if the
+	expression is non-zero, it shows the warning message such as
 	<computeroutput>BUG? (xxx)</computeroutput>
-	normally followed by stack trace.  It returns the evaluated
-	value.
-	When no <constant>CONFIG_SND_DEBUG</constant> is set, this
-	macro always returns zero.
+	normally followed by stack trace.
+
+	In both cases it returns the evaluated value.
       </para>
 
     </section>