Revert "bionic: Allocate a shadow call stack for each thread."
This reverts commit 65c84848.
Causes mmap/malloc failure after creating many threads.
Test: Play music change tracks, then attempt Camera video record.
Bug: 118593766
Change-Id: I6287752d35dd31124c21708e94fddce9facdbf6d
(cherry picked from commit 75302dbc)