ensure g_dfu is linked to start of RAM when building DFU loader
diff --git a/firmware/libboard/common/resources/sam3s2/flash.ld b/firmware/libboard/common/resources/sam3s2/flash.ld
index 22cfe59..5b52273 100644
--- a/firmware/libboard/common/resources/sam3s2/flash.ld
+++ b/firmware/libboard/common/resources/sam3s2/flash.ld
@@ -109,6 +109,8 @@
     {
         . = ALIGN(4);
         _srelocate = .;
+        /* we must make sure the .dfudata is linked to start of RAM */
+        *(.dfudata .dfudata.*);
         *(.ramfunc .ramfunc.*);
         *(.data .data.*);
         . = ALIGN(4);