[S390] reset default for CONFIG_CHSC_SCH

6f9a3c33 "[S390] cleanup s390 Kconfig" accidentally changed
the default for CONFIG_CHSC_SCH. Reset it to m.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Kconfig

@@ -406,7 +406,7 @@ config QDIO
 	  If unsure, say Y.
 
 config CHSC_SCH
-	def_tristate y
+	def_tristate m
 	prompt "Support for CHSC subchannels"
 	help
 	  This driver allows usage of CHSC subchannels. A CHSC subchannel