drivers: sensor: adxl362: make time configurable via KConfig

The thresholds for activity/inactivity in the adxl362 acceleromter have
two parameters that can be configured. Currently the threshold is
configurable via the KConfig variables CONFIG_ADXL362_ACTIVITY_THRESHOLD
and CONFIG_ADXL362_INACTIVITY_THRESHOLD which configure repectively the
value in the THRESH_ACT and THRESH_INACT registers.
The other parameter that can be configured is the time by changing the
values in the registers TIME_ACT and TIME_INACT, but this values are
hardcoded to 1 (see lines 653 and 675 in adxl362.c), this patch adds
support for configuring those values in KConfig as
CONFIG_ADXL362_ACTIVITY_TIME and CONFIG_ADXL362_INACTIVITY_TIME.

Signed-off-by: Xavier Naveira <xnaveira@gmail.com>