slimbus: Fix out-of-bounds access in slim_slicesize()

With gcc-4.1.2:

    slimbus/messaging.c: In function ‘slim_slicesize’:
    slimbus/messaging.c:186: warning: statement with no effect

Indeed, clamp() is a macro not operating in-place, but returning the
clamped value.  Hence the value is not clamped at all, which may lead to
an out-of-bounds access.

Fix this by assigning the clamped value.

Fixes: afbdcc7c38 ("slimbus: Add messaging APIs to slimbus framework")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/slimbus/messaging.c

@@ -183,7 +183,7 @@ static u16 slim_slicesize(int code)
 		0, 1, 2, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7
 	};
 
-	clamp(code, 1, (int)ARRAY_SIZE(sizetocode));
+	code = clamp(code, 1, (int)ARRAY_SIZE(sizetocode));
 
 	return sizetocode[code - 1];
 }