Add an explicit dependency on checkprogsize target for the final binary

Author: valeros

builder/main.py

@@ -231,6 +231,7 @@ def __fetch_spiffs_size(target, source, env):
     else:
         target_firm = env.ElfToBin(
             join("$BUILD_DIR", "${PROGNAME}"), target_elf)
+        env.Depends(target_firm, "checkprogsize")
 
 env.AddPlatformTarget("buildfs", target_firm, target_firm, "Build Filesystem Image")
 AlwaysBuild(env.Alias("nobuild", target_firm))