elf2flt: fix threading apps on ARM noMMU systems

See this thread, which explains the problem in detail:
http://mailman.uclinux.org/pipermail/uclinux-dev//2016-April/052713.html



Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>