ASoC: soc-core: check ops & auto_selectable_formats in snd_soc_dai_get_fmt() to prevent dereference error

Smatch reported an issue that "ops" could be null (see
line 174) where later "ops" is dereferenced to extract
the dai fmts, also auto_selectable_formats can also be
null.

Add a proper null check before accessing both the ptrs
to ensure a safe execution.

Signed-off-by: HariKrishna Sagala <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/soc-dai.c

···
 	if (max < until)
 		until = max;
 
-	for (i = 0; i < until; i++)
-		fmt |= ops->auto_selectable_formats[i];
+	if (ops && ops->auto_selectable_formats)
+		for (i = 0; i < until; i++)
+			fmt |= ops->auto_selectable_formats[i];
 
 	return fmt;
 }