misc: xilinx-sdfec: fix dependency and build error

lib/devres.c, which implements devm_ioremap_resource(), is only built
when CONFIG_HAS_IOMEM is set/enabled, so XILINX_SDFEC should depend
on HAS_IOMEM.  Fixes this build error (as seen on UML builds):

ERROR: "devm_ioremap_resource" [drivers/misc/xilinx_sdfec.ko] undefined!

Fixes: 76d83e1c32 ("misc: xilinx-sdfec: add core driver")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Derek Kiernan <derek.kiernan@xilinx.com>
Cc: Dragan Cvetic <dragan.cvetic@xilinx.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/f9004be5-9925-327b-3ec2-6506e46fe565@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/Kconfig

@@ -465,6 +465,7 @@ config PCI_ENDPOINT_TEST
 
 config XILINX_SDFEC
 	tristate "Xilinx SDFEC 16"
+	depends on HAS_IOMEM
 	help
 	  This option enables support for the Xilinx SDFEC (Soft Decision
 	  Forward Error Correction) driver. This enables a char driver