Fix avr-objcopy error.

Makefile

@@ -553,7 +553,7 @@ extcoff: $(BINDIR)/$(TARGET).elf
 %.eep: %.elf
 #	@echo
 	@echo $(MSG_EEPROM) $@
-	@-$(OBJCOPY) -j .eeprom --set-section-flags=.eeprom="alloc,load" \
+	@-$(OBJCOPY) -j .eeprom --set-section-flags=.eeprom='alloc,load' \
 	--change-section-lma .eeprom=0 --no-change-warnings -O $(FORMAT) $< $@ || exit 0
 
 # Create extended listing file from ELF output file.