firmware-utils: mkfwimage: enable extra compiler checks and fix them

Let's enforce additional automatic checks enforced by the compiler in
order to catch possible errors during compilation.

Signed-off-by: Petr Štetiar <ynezz@true.cz>

tools/firmware-utils/Makefile

@@ -12,7 +12,13 @@ include $(INCLUDE_DIR)/host-build.mk
 include $(INCLUDE_DIR)/kernel.mk
 
 define cc
-	$(HOSTCC) $(HOST_CFLAGS) -include endian.h $(HOST_LDFLAGS) -o $(HOST_BUILD_DIR)/bin/$(firstword $(1)) $(foreach src,$(1),src/$(src).c) $(2)
+	$(HOSTCC) \
+		$(HOST_CFLAGS) \
+		-Wno-unused-parameter \
+		-include endian.h $(HOST_LDFLAGS) \
+		-o $(HOST_BUILD_DIR)/bin/$(firstword $(1)) \
+		$(foreach src,$(1),src/$(src).c) \
+		$(2)
 endef
 
 define Host/Compile
@@ -32,7 +38,7 @@ define Host/Compile
 	$(call cc,mkzynfw)
 	$(call cc,lzma2eva,-lz)
 	$(call cc,mkcasfw)
-	$(call cc,mkfwimage,-lz -Wall)
+	$(call cc,mkfwimage,-lz -Wall -Werror -Wextra)
 	$(call cc,mkfwimage2,-lz)
 	$(call cc,imagetag imagetag_cmdline cyg_crc32)
 	$(call cc,add_header)

tools/firmware-utils/src/mkfwimage.c

@@ -262,7 +262,8 @@ static void usage(const char* progname)
 
 static void print_image_info(const image_info_t* im)
 {
-	int i = 0;
+	unsigned int i = 0;
+
 	INFO("Firmware version: '%s'\n"
 	     "Output file: '%s'\n"
 	     "Part count: %u\n",
@@ -279,8 +280,6 @@ static void print_image_info(const image_info_t* im)
 	}
 }
 
-
-
 static u_int32_t filelength(const char* file)
 {
 	FILE *p;
@@ -336,7 +335,7 @@ static int create_image_layout(const char* kernelfile, const char* rootfsfile, c
  */
 static int validate_image_layout(image_info_t* im)
 {
-	int i;
+	unsigned int i;
 
 	if (im->part_count == 0 || im->part_count > MAX_SECTIONS)
 	{
@@ -383,7 +382,7 @@ static int build_image(image_info_t* im)
 	char* ptr;
 	u_int32_t mem_size;
 	FILE* f;
-	int i;
+	unsigned int i;
 
 	// build in-memory buffer
 	mem_size = sizeof(header_t);