[PATCH -next] thermal: fix mtk_thermal build dependency

[Randy Dunlap]

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

Fix build errors when MTK_THERMAL=y and NVMEM=m by preventing that
Kconfig combination.

drivers/built-in.o: In function `mtk_thermal_probe':
mtk_thermal.c:(.text+0xffa8f): undefined reference to `nvmem_cell_get'
mtk_thermal.c:(.text+0xffabe): undefined reference to `nvmem_cell_read'
mtk_thermal.c:(.text+0xffac9): undefined reference to `nvmem_cell_put'

Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Zhang Rui <rui.zhang@xxxxxxxxx>
Cc: Eduardo Valentin <edubezval@xxxxxxxxx>
Cc: <linux-pm@xxxxxxxxxxxxxxx>
Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
Cc: Hanyi Wu <hanyi.wu@xxxxxxxxxxxx>
---
 drivers/thermal/Kconfig |    1 +
 1 file changed, 1 insertion(+)

--- linux-next-20160419.orig/drivers/thermal/Kconfig
+++ linux-next-20160419/drivers/thermal/Kconfig
@@ -366,6 +366,7 @@ config MTK_THERMAL
 	tristate "Temperature sensor driver for mediatek SoCs"
 	depends on ARCH_MEDIATEK || COMPILE_TEST
 	depends on HAS_IOMEM
+	depends on NVMEM || NVMEM=n
 	default y
 	help
 	  Enable this option if you want to have support for thermal management