zephyr: turn off I2C
Upstream Zephyr is making a habit of enabling subsystems on any board
that supports them. That's a potential security risk if any of those
allow interference with the running bootloader, and is currently
exceeding mcuboot's flash allowance on some STM32 targets,
e.g. 96b_carbon. Turn off I2C to restore the build for those.
Signed-off-by: Marti Bolivar <marti.bolivar@linaro.org>
diff --git a/boot/zephyr/prj.conf b/boot/zephyr/prj.conf
index 510fe90..27efab5 100644
--- a/boot/zephyr/prj.conf
+++ b/boot/zephyr/prj.conf
@@ -14,7 +14,8 @@
CONFIG_FLASH=y
CONFIG_MPU_ALLOW_FLASH_WRITE=y
-### Disable Bluetooth by default
-# CONFIG_BT is not set
-
CONFIG_MULTITHREADING=n
+
+### Zephyr keeps turning on major subsystems by default that we don't want.
+# CONFIG_BT is not set
+# CONFIG_I2C is not set