tty: mips_ejtag_fdc: use u8 for character pointers

mips_ejtag_fdc_encode() and mips_ejtag_fdc_put_chan() declare arrays of
pointers to characters. Switch their types from char to u8 to conform
to the current tty layer types for characters.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20231206073712.17776-16-jirislaby@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>