auxdisplay: Fix duplicate CHARLCD config symbol

A second CHARLCD config symbol was added instead of moving the existing
one.  Fix this by removing the old one.

Fixes: 718e05ed ("auxdisplay: Introduce hd44780_common.[ch]")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>