Reduce code size for accelerometer support (#288)

* Reduce the LIS2DH12 driver's code size.
* Reduce the MMA8652FC driver's code size.
* Make orientation detection smaller.


* Inlined C++ class constructor.
* De-unroll I2C register writes.
* Removed unused setSensitivity method.

workspace/TS100/inc/hardware.h

@@ -13,6 +13,12 @@
 extern "C" {
 #endif
 
+enum Orientation {
+    ORIENTATION_LEFT_HAND = 0,
+    ORIENTATION_RIGHT_HAND = 1,
+    ORIENTATION_FLAT = 3
+};
+
 #define KEY_B_Pin GPIO_PIN_6
 #define KEY_B_GPIO_Port GPIOA
 #define TMP36_INPUT_Pin GPIO_PIN_7