sm8250-common: vibrator: Implement OOS style effects for LED vibrator

This change implements the following effects:
- Effect::CLICK
- Effect::DOUBLE_CLICK
- Effect::TICK
- Effect::HEAVY_CLICK

Effect write streams were dumped using following strace command:
- strace -fp `pidof vendor.oneplus.hardware.lmvibrator@1.0-service` -e openat,write

Also, these effects can easily be tested with following test app:
- https://github.com/luk1337/VibeTest

Change-Id: Ie65caa0c65dc81bb35a7bcc56870649e895ced3f

vibrator/include/Vibrator.h

@@ -60,7 +60,6 @@ public:
     int on(int32_t timeoutMs);
     int off();
     bool mDetected;
-private:
     int write_value(const char *file, const char *value);
 };