Convert CONFIG_IMX_BOOTAUX et al to Kconfig

This converts the following to Kconfig:
   CONFIG_IMX_BOOTAUX
   CONFIG_IMX_THERMAL

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/seeed_npi_imx6ull_defconfig b/configs/seeed_npi_imx6ull_defconfig
index f08542a..6489e8b 100644
--- a/configs/seeed_npi_imx6ull_defconfig
+++ b/configs/seeed_npi_imx6ull_defconfig
@@ -66,5 +66,6 @@
 CONFIG_DM_REGULATOR_FIXED=y
 CONFIG_DM_REGULATOR_GPIO=y
 CONFIG_MXC_UART=y
+CONFIG_IMX_THERMAL=y
 CONFIG_USB=y
 CONFIG_USB_GADGET=y