AP_Notify: remove non-required initialisation of variables

These objects are dynamically allocated, and we zero the memory
as we allocate them

libraries/AP_Notify/Display.cpp

@@ -324,9 +324,6 @@ bool Display::init(void)
         return true;
     }
 
-    _mstartpos = 0; // ticker shift position
-    _movedelay = 4; // ticker delay before shifting after new message displayed
-
     // initialise driver
     for(uint8_t i=0; i<8 && _driver == nullptr; i++) {
         if (! (I2C_BUS_PROBE_MASK & (1<<i))) {

libraries/AP_Notify/Display.h

@@ -34,8 +34,8 @@ private:
 
     bool _healthy;
 
-    uint8_t _mstartpos;
-    uint8_t _movedelay;
+    uint8_t _mstartpos; // ticker shift position
+    uint8_t _movedelay; // ticker delay before shifting after new message displayed
     uint8_t _screenpage;
 
     // stop showing text in display after this many millis: