ASoC: fsi: tidyup: remove un-necessary operation from fsi_probe()

struct fsi_master *master became member of struct fsi_priv from
71f6e0645be42f93c0f90dfcc93b9d2d277c2ee6
(ASoC: sh_fsi: avoid using global variable)

So, master = NULL is not necessary on fsi_probe() now.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/sh/fsi.c

@@ -1738,7 +1738,6 @@ exit_iounmap:
 	iounmap(master->base);
 exit_kfree:
 	kfree(master);
-	master = NULL;
 exit:
 	return ret;
 }