Fix 'F' morse code representation - currently is same as 'L'. First noticed by K7OME

Author: rnighting

morse.cpp

@@ -20,7 +20,7 @@ static const PROGMEM struct Morse morse_table[] = {
 {'c', 0xea}, // 11101010
 {'d', 0xf4}, // 11110100
 {'e', 0xfc}, // 11111100
-{'f', 0xe4}, // 11100100
+{'f', 0xe2}, // 11100010
 {'g', 0xf6}, // 11110110
 {'h', 0xe0}, // 11100000
 {'i', 0xf8}, // 11111000