drivers: flash : introduce a new driver for the OCTOSPI

This is the stm32 octospi driver based on the exisitng quadspi
 for stm32 devices and source code from the STM32Cube.
This drivers initialized the peripheral and the NOR memory
in SPI or OctoSPI mode with STR or DTR data Transfer rates.
The NOR-flash can provide the SDFP table directly (if supported)
or through the DeviceTree.
 Limitation: no DMA transfer.

Signed-off-by: Francois Ramu <francois.ramu@st.com>