Makefile: Pack e2fsdroid into otatools.zip.

e2fsdroid is needed to create ext4 images with mke2fs. Also pack both
sets of mke2fs and make_ext4fs tools into otatools.zip. Because we use
the latest otatools.zip to create OTAs, which needs to handle
target_files.zip using either of them.

Bug: 34126605
Test: `m otatools-package` and check it has e2fsdroid and make_ext4fs.
Test: Use otatools.zip to sign a TF.zip that defines
      TARGET_USES_MKE2FS={true,false}.

Change-Id: I9967e4f078cbe912914c6c511681cba82356ae8e