Remove unused declaration of Fl_Char

FL/Fl_Input_.H

@@ -242,8 +242,8 @@ public:
   */
   const char* value() const {return value_;}
 
-  /* Returns the character at index \p i. */
-  Fl_Char index(int i) const;
+  /* Returns the Unicode character at index \p i. */
+  unsigned int index(int i) const;
 
   /**
     Returns the number of bytes in value().

FL/fl_types.h

@@ -52,9 +52,6 @@ typedef unsigned long ulong;
 */
 typedef unsigned int Fl_Shortcut;
 
-/** 24-bit Unicode character - upper 8 bits are unused */
-typedef unsigned int Fl_Char;
-
 /*@}*/  /* group: Miscellaneous */
 
 #endif