Kconfig: Add new WANT_I2C option to reduce code size

Make it possible to not compile in support for I2C on chips with small
flash sizes.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

src/Kconfig

@@ -96,6 +96,14 @@ config WANT_SOFTWARE_SPI
     bool
     depends on WANT_SPI
     default y
+config WANT_I2C
+    bool
+    depends on HAVE_GPIO && HAVE_GPIO_I2C
+    default y
+config WANT_SOFTWARE_I2C
+    bool
+    depends on WANT_I2C
+    default y
 config WANT_HARD_PWM
     bool
     depends on HAVE_GPIO_HARD_PWM
@@ -134,15 +142,15 @@ config WANT_ADXL345
     default y
 config WANT_LIS2DW
     bool
-    depends on WANT_SPI || HAVE_GPIO_I2C
+    depends on WANT_SPI || WANT_I2C
     default y
 config WANT_MPU9250
     bool
-    depends on HAVE_GPIO_I2C
+    depends on WANT_I2C
     default y
 config WANT_ICM20948
     bool
-    depends on HAVE_GPIO_I2C
+    depends on WANT_I2C
     default y
 config WANT_HX71X
     bool
@@ -154,16 +162,12 @@ config WANT_ADS1220
     default y
 config WANT_LDC1612
     bool
-    depends on HAVE_GPIO_I2C
+    depends on WANT_I2C
     default y
 config WANT_SENSOR_ANGLE
     bool
     depends on WANT_SPI
     default y
-config WANT_SOFTWARE_I2C
-    bool
-    depends on HAVE_GPIO && HAVE_GPIO_I2C
-    default y
 config NEED_SENSOR_BULK
     bool
     depends on WANT_ADXL345 || WANT_LIS2DW || WANT_MPU9250 || WANT_ICM20948 \
@@ -177,6 +181,12 @@ config WANT_SPI
 config WANT_SOFTWARE_SPI
     bool "Support software based SPI \"bit-banging\""
     depends on WANT_SPI
+config WANT_I2C
+    bool "Support communicating with external chips via I2C bus"
+    depends on HAVE_GPIO && HAVE_GPIO_I2C
+config WANT_SOFTWARE_I2C
+    bool "Support software based I2C \"bit-banging\""
+    depends on WANT_I2C
 config WANT_HARD_PWM
     bool "Support hardware PWM (pulse width modulation)"
     depends on HAVE_GPIO_HARD_PWM
@@ -206,13 +216,13 @@ config WANT_ADXL345
     depends on WANT_SPI
 config WANT_LIS2DW
     bool "Support lis2dw and lis3dh 3-axis accelerometers"
-    depends on WANT_SPI || HAVE_GPIO_I2C
+    depends on WANT_SPI || WANT_I2C
 config WANT_MPU9250
     bool "Support MPU accelerometers"
-    depends on HAVE_GPIO_I2C
+    depends on WANT_I2C
 config WANT_ICM20948
     bool "Support ICM20948 accelerometer"
-    depends on HAVE_GPIO_I2C
+    depends on WANT_I2C
 config WANT_HX71X
     bool "Support HX711 and HX717 ADC chips"
     depends on HAVE_GPIO
@@ -221,13 +231,10 @@ config WANT_ADS1220
     depends on WANT_SPI
 config WANT_LDC1612
     bool "Support ldc1612 eddy current sensor"
-    depends on HAVE_GPIO_I2C
+    depends on WANT_I2C
 config WANT_SENSOR_ANGLE
     bool "Support angle sensors"
     depends on WANT_SPI
-config WANT_SOFTWARE_I2C
-    bool "Support software based I2C \"bit-banging\""
-    depends on HAVE_GPIO && HAVE_GPIO_I2C
 endmenu
 
 # Generic configuration options for CANbus