stm32mp: add DT helper for reg by name

Add a new entry to find register properties by name and
include new assert functions to limit address cells to 1
and size cells to 1.

Change-Id: Ide59a795a05fb2af36bd07fec15e5a3adf196226
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
diff --git a/plat/st/common/include/stm32mp_dt.h b/plat/st/common/include/stm32mp_dt.h
index 74b01b3..a29d914 100644
--- a/plat/st/common/include/stm32mp_dt.h
+++ b/plat/st/common/include/stm32mp_dt.h
@@ -32,6 +32,8 @@
 				 uint32_t dflt_value);
 int fdt_read_uint32_array(int node, const char *prop_name,
 			  uint32_t *array, uint32_t count);
+int fdt_get_reg_props_by_name(int node, const char *name, uintptr_t *base,
+			      size_t *size);
 int dt_set_stdout_pinctrl(void);
 void dt_fill_device_info(struct dt_node_info *info, int node);
 int dt_get_node(struct dt_node_info *info, int offset, const char *compat);