disk: disk_access_flash: align buffer
disk: disk_access_flash: align buffer

Flash drivers may impose alignment requirements on the destination
buffers due to use of DMA transfers.  In particular Nordic QSPI flash
API requires that addresses, sizes, and buffers all be 4-byte aligned.
Align the ready/copy buffer to satisfy this requirement.

Signed-off-by: Peter A. Bigot <650538893330be855f76604594b4820eb226769e@pabigot.com>

Vudentz/zephyr,nashif/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,finikorg/zephyr,Vudentz/zephyr,galak/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr