Revert "Convert dexdeps-docs to Soong."

This reverts commit 06c4151b.

Reason for revert: Fix ndk build for many targets

For example:
https://android-build.googleplex.com/builds/quarterdeck?branch=aosp-master&target=ndk&lkbb=4925048&lkgb=4924880&fkbb=4924952

Sample error log:
Buildbot Version: androidbuild_buildbot_20180726.00_RC00
Machine: wphn2.hot.corp.google.com
OUT_DIR=out DIST_DIR=/buildbot/dist_dirs/git_oc-mr1-dev-plus-aosp-linux-ndk/4924977 build/soong/scripts/build-ndk-prebuilts.sh
FAILED: ninja: out/soong/build.ninja:1876642: multiple rules generate out/soong/target/product/generic_arm64/system/bin/dexdeps [-w dupbuild=err]
08:26:59 ninja failed with: exit status 1
Return Code: 1

Change-Id: I64db83ba76076edd0e4b370074d7aaf0854af6bb