Create parent directories before writing to output target files

Sometimes the output path's parent directory doesn't exist yet,
causing a failure in open() syscall.

Test: sign_target_files_apks solios-target_files-12328286.zip
solis_signed.zip
Bug: 364967828

Change-Id: I85f91ca5d1321c1ba763cac058eb28acc7f48e70

tools/releasetools/common.py

@@ -3238,7 +3238,9 @@ class File(object):
     return t
 
   def WriteToDir(self, d):
-    with open(os.path.join(d, self.name), "wb") as fp:
+    output_path = os.path.join(d, self.name)
+    os.makedirs(os.path.dirname(output_path), exist_ok=True)
+    with open(output_path, "wb") as fp:
       fp.write(self.data)
 
   def AddToZip(self, z, compression=None):