INT 21 - DOS 4+ - COUNTRY-DEPENDENT CHARACTER CAPITALIZATION
        AH = 65h
        AL = function
            20h capitalize character
                DL = character to capitalize
                Return: DL = capitalized character
            21h capitalize string
                DS:DX -> string to capitalize
                CX = length of string
            22h capitalize ASCIZ string
                DS:DX -> ASCIZ string to capitalize
Return: CF set on error
            AX = error code (see AH=59h)
        CF clear if successful
Note:   these calls have been documented for DOS 5+, but were undocumented in
          DOS 4.x.

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