memory: jz4780-nemc: Do not build by default

Enabling the JZ4780_NEMC driver makes sense only for specific hardware -
the Ingenic SoC architecture.  It is not an essential driver for the SoC
support so do not enable it by default.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

drivers/memory/Kconfig

@@ -141,7 +141,6 @@ config FSL_IFC
 
 config JZ4780_NEMC
 	bool "Ingenic JZ4780 SoC NEMC driver"
-	default y
 	depends on MIPS || COMPILE_TEST
 	depends on HAS_IOMEM && OF
 	help