binutils/binutils: do not forget to extract elf2flt

In case we're using a custom (aka local) binutils source, we still
need to extract and patch elf2flt.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 reporter_name="Yann Diorcet <diorcet.yann@gmail.com>"

 reporter_url=""

 reporter_comment="Config to build cross-compiler with mingw as kernel type for

 32 bits Windows target"