serial: sc16is7xx: use DECLARE_BITMAP for sc16is7xx_lines bitfield

Replace the explicit sc16is7xx_lines bitfield declaration with the generic
macro DECLARE_BITMAP() to reserve just enough memory to contain all
required bits.

This also improves code self-documentation by showing the maximum number
of bits required.

This conversion now makes sc16is7xx_lines an array, so drop the "&" before
sc16is7xx_lines in all bit access functions.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231221231823.2327894-7-hugo@hugovil.com


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