Revert "build: remove .SECONDARY"

This reverts commit 93a520b9665193659edd953021b18c394065328f.  According to
Nadav's analisys, .SECONDARY was not at fault (it was libstatic-thread-local.so
trying to link against itself; fixed by a4b52857d38.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>