[Print] Fixed issues found by cppcheck

src/protocols/Print/ITA2String.cpp

@@ -46,6 +46,9 @@ uint8_t* ITA2String::byteArr() {
     uint8_t* temp = new uint8_t[asciiLen*2 + 1];
   #endif
 
+  // ensure the minimum possible array size is always initialized
+  temp[0] = 0;
+  
   size_t arrayLen = 0;
   bool flagFigure = false;
   for(size_t i = 0; i < asciiLen; i++) {

src/protocols/Print/ITA2String.h

@@ -27,13 +27,13 @@ class ITA2String {
       \brief Default single-character constructor.
       \param c ASCII-encoded character to encode as ITA2.
     */
-    ITA2String(char c);
+    explicit ITA2String(char c);
 
     /*!
       \brief Default string constructor.
       \param str ASCII-encoded string to encode as ITA2.
     */
-    ITA2String(const char* str);
+    explicit ITA2String(const char* str);
 
     /*!
       \brief Default destructor.

src/protocols/Print/Print.h

@@ -19,11 +19,11 @@ class RadioLibPrint {
     virtual size_t write(uint8_t) = 0;
     size_t write(const char *str) {
       if (str == NULL) return 0;
-      return write((const uint8_t *)str, strlen(str));
+      return write(reinterpret_cast<const uint8_t *>(str), strlen(str));
     }
     virtual size_t write(const uint8_t *buffer, size_t size);
     size_t write(const char *buffer, size_t size) {
-      return write((const uint8_t *)buffer, size);
+      return write(reinterpret_cast<const uint8_t *>(buffer), size);
     }
 
     size_t print(ITA2String& ita2);
@@ -60,7 +60,7 @@ class RadioLibPrint {
   protected:
 #endif
     uint8_t encoding = RADIOLIB_ASCII_EXTENDED;
-    const char* lineFeed;
+    const char* lineFeed = "\r\n";
 
     size_t printNumber(unsigned long, uint8_t);
     size_t printFloat(double, uint8_t);