init: init_defaults uses more shared libraries.

This CL switches init_defaults and thus init_second_stage to depend on
commonly used shared libraries. In particular, use the following shared
libs that have been available on device (under both of normal boot and
recovery):
 - libbootloader_message
 - libext4_utils
 - libfs_mgr
 - libhidl-gen-utils
 - libkeyutils
 - liblogwrap

The following transitive dependencies have been dropped. They were only
needed when including the above libs statically. Dropping them doesn't
further affect the size though.
 - libfec
 - libfec_rs
 - libsquashfs_utils

With the change, the second stage init size has been reduced from
1094328 to 627992 bytes (aosp_taimen-userdebug), with no new shared libs
installed.

Also evaluated the impact of using `libprotobuf-cpp-lite.so` and
`libseccomp_policy.so`. It doesn't look beneficial -- at least not right
now with `init` as the singler user.
 - statically linked them both: 627992-byte
 - with libprotobuf-cpp-lite.so: 605880 (init) + 262624 (.so)
 - with libseccomp_policy.so: 605848 (init) + 32208 (.so)

Bug: 112494634
Test: `mmma -j system/core/init` with aosp_marlin-userdebug
Test: Flash the marlin build on device. Run init_test.
Test: Boot into recovery successfully.
Change-Id: I49debe9066ff36dfda55b08266862e29e2bfc96b