drivers: audio: mpxxdtyy: Handle PCM block sizes of more than 1 ms

The Open_PDM_Filter_64/128() functions of the third-party OpenPDMFilter
library are designed to handle a fixed PCM block size of 1 ms of audio.
Allow the MPxxDTyy drivers to use a block size of more than 1 ms by
calling the filtering function multiple times, once for each ms of
audio.

Fixes zephyrproject-rtos/zephyr#69447

Signed-off-by: Petar Susac <petar.susac@byte-lab.com>