reset: imx7: add 'depends on HAS_IOMEM' to fix unmet dependency

This config select's MFD_SYSCON, but does not depend on HAS_IOMEM.

Compile testing on architecture without HAS_IOMEM causes "unmet
direct dependencies" in Kconfig phase.

Detected by "make ARCH=score allyesconfig".
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>

drivers/reset/Kconfig

@@ -49,6 +49,7 @@ config RESET_HSDK
 
 config RESET_IMX7
 	bool "i.MX7 Reset Driver" if COMPILE_TEST
+	depends on HAS_IOMEM
 	default SOC_IMX7D
 	select MFD_SYSCON
 	help