common: rename functions lcd_dt_simplefb to fdt_simplefb

Rename the function named lcd_dt_simplefb* to fdt_simplefb* to be aligned
with the associated file name fdt_simplefb.h/fdt_simplefb.c

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
diff --git a/include/fdt_simplefb.h b/include/fdt_simplefb.h
index 7cc305e..7e54723 100644
--- a/include/fdt_simplefb.h
+++ b/include/fdt_simplefb.h
@@ -8,6 +8,6 @@
 
 #ifndef _FDT_SIMPLEFB_H_
 #define _FDT_SIMPLEFB_H_
-int lcd_dt_simplefb_add_node(void *blob);
-int lcd_dt_simplefb_enable_existing_node(void *blob);
+int fdt_simplefb_add_node(void *blob);
+int fdt_simplefb_enable_existing_node(void *blob);
 #endif