driver: sensor: adxl362: Bug fix for q31_t conv

This is a bug fix for adxl362_temp_convert_q31 and
adxl362_accel_convert_q31 functions.
Functions are used to convert samples received from
sensor to q31_t format when RTIO stream is used.

Signed-off-by: Vladislav Pejic <vladislav.pejic@orioninc.com>