misc: open-dice: make OPEN_DICE depend on HAS_IOMEM

On s390 systems (aka mainframes), it has classic channel devices for
networking and permanent storage that are currently even more common
than PCI devices. Hence it could have a fully functional s390 kernel
with CONFIG_PCI=n, then the relevant iomem mapping functions
[including ioremap(), devm_ioremap(), etc.] are not available.

Here let OPEN_DICE depend on HAS_IOMEM so that it won't be built
to cause below compiling error if PCI is unset:

------
ERROR: modpost: "devm_memremap" [drivers/misc/open-dice.ko] undefined!
ERROR: modpost: "devm_memunmap" [drivers/misc/open-dice.ko] undefined!
------

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202306211329.ticOJCSv-lkp@intel.com/
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Derek Kiernan <derek.kiernan@amd.com>
Cc: Dragan Cvetic <dragan.cvetic@amd.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230707135852.24292-4-bhe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/Kconfig

@@ -496,6 +496,7 @@ config HISI_HIKEY_USB
 config OPEN_DICE
 	tristate "Open Profile for DICE driver"
 	depends on OF_RESERVED_MEM
+	depends on HAS_IOMEM
 	help
 	  This driver exposes a DICE reserved memory region to userspace via
 	  a character device. The memory region contains Compound Device