samples: drivers: spi_flash: stm32: fix dma DTS phandle lists

Correct stm32h573i_dk DTS overlay file DMA list that was not split
by phandle and seemed to form unique phandle. This is not currently
an issue with existing DT parsing macros and tools but may generate
build errors if tools are more strict on the DTS implementation format.

Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
1 file changed