lcd: replace CONSOLE_(ROWS|COLS) with variables

lcd: replace CONSOLE_(ROWS|COLS) with variables

Replace CONSOLE_(ROWS|COLS) macros with variables, and assign the
original macro values.

This is a preparatory step for extracting lcd console code into its own
file.

Signed-off-by: Nikita Kiryanov <[email protected]>
Cc: Anatolij Gustschin <[email protected]>
Cc: Simon Glass <[email protected]>
Acked-by: Simon Glass <[email protected]>
Tested-by: Simon Glass <[email protected]>