Look into ld_preloads before current library

 Change lookup order during relocation so that
 ld_preloads always precede caller (unless caller
 is main executable).

 Asan needs this change in order to intercept libc->libc
 calls.

Bug: 15432753
Change-Id: If69aa16efe59aa35bb30e96feb83d08f1efbec86