s390/jump label,nss: let shared kernel support depend on !JUMP_LABEL

We can have either shared kernel or jump label support, but not both.
If a kernel gets IPL'ed from an NSS it's not possible to patch the
text segment, since it's read-only.
Therefore any static branches cannot be updated. So we need to make
sure that shared kernel support is disabled if jump label support
is enabled.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Kconfig

@@ -545,8 +545,8 @@ config PFAULT
 	  this option.
 
 config SHARED_KERNEL
-	def_bool y
-	prompt "VM shared kernel support"
+	bool "VM shared kernel support"
+	depends on !JUMP_LABEL
 	help
 	  Select this option, if you want to share the text segment of the
 	  Linux kernel between different VM guests. This reduces memory