[S390] Kconfig: refine depends statements.

Refine some depends statements to limit their visibility to the
environments that are actually supported.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
index 0300e7f5..2e18a63e 100644
--- a/drivers/auxdisplay/Kconfig
+++ b/drivers/auxdisplay/Kconfig
@@ -6,6 +6,7 @@
 #
 
 menu "Auxiliary Display support"
+	depends on PARPORT
 
 config KS0108
 	tristate "KS0108 LCD Controller"