refactor(stm32mp1): move DT_UART_COMPAT in include file

Move the definition of DT_UART_COMPAT in stm32mp1_def.h to be used
in several files.

Change-Id: I74d0350bcd971df9b15697f2b9ec04061d6a7656
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
2 files changed