serial: Rename uart_change_speed() to uart_change_line_settings()

serial: Rename uart_change_speed() to uart_change_line_settings()

[ Upstream commit 826736a6c7c8c3185bfb10e03c10d03d53d6cf94 ]

uart_change_speed() changes more than just speed so rename it to more
generic uart_change_line_settings().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 8679328eb859 ("serial: Reduce spinlocked portion of uart_rs485_config()")
Signed-off-by: Sasha Levin <sashal@kernel.org>