"bootstrap: true" modules are using bootstrap Bionic

If the bootstrap property is set to true, a binary configured to refer
to the bootstrap linker at /system/bin/bootstrap/linker[64]. This is for
very early processes that are executed before the init makes the linker
by bind-mounting it.

Bug: 120266448
Test: m init_second_stage and use readelf on the built file
DT_INTERP is set to /system/bin/bootstrap/linker64 and

Change-Id: I67487701192f127679cc8127ddc9f53e102ba9c4