Fix bit ordering in C header

Author: micprog

target/common/common.mk

@@ -84,7 +84,7 @@ $(SN_GEN_DIR) $(SN_BIN_DIR):
 # $1: target name, $2: prerequisite (hjson description file)
 define peakrdl_generate_header
 	@echo "[peakRDL] Generating $1"
-	$(PEAKRDL) c-header -b htol $2 -o $1
+	$(PEAKRDL) c-header -b ltoh $2 -o $1
 	@$(CLANG_FORMAT) -i $1
 endef