On Ideapad laptops, ACPI event 1 is currently not handled. Many models
log "ideapad_laptop: Unknown event: 1" every 20 seconds or so while
running on battery power. Some convertible laptops receive this event
when switching in and out of tablet mode.

This adds and additional case for event 1 in ideapad_acpi_notify to call
ideapad_input_report(priv, vpc_bit), so that the event is reported to
userspace and we avoid unnecessary logging.

Fixes bug #107481 (https://bugzilla.kernel.org/show_bug.cgi?id=107481)
Fixes bug #65751 (https://bugzilla.kernel.org/show_bug.cgi?id=65751)
Signed-off-by: Zach Ploskey <zach@ploskey.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>