Reenable support for non-PIE executables

On Nakasi builds, /system/bin/tf_daemon is a pre-compiled
vendor supplied binary. When support for non-PIE executables
was removed, that daemon failed to start, which induced
a number of bugs.

  * keystore is broken
  * CTS runs will hang after a certain period of time

Temporarily reenable non-PIE support for 32-bit platforms
until Nakasi is fixed.

This rolls back the following commits:

  Cleanup: updated comments
  * 6275f2083415d22a6ce0de55645079cd47e0cc80
  Cleanup: remove AARCH/ARM_COPY relocation support
  * b906e13c55c9fe9b4157ba548534a0230434882b

And restricts the following patch to 64 bit only:

  Remove support for non-PIE executables
  * 2aebf5429bb1241a3298b5b642d38f73124c2026

Bug: 14566672
Bug: 15086752
Bug: 15732002
Change-Id: Ia2501aa14bd30feb4a6ce66bdb7c9f066dba0b5f