elf: Move note processing after l_phdr is updated

Program headers are processed in two pass: after the first pass
load segments are mmapped so in the second pass target specific
note processing logic can access the notes.

The second pass is moved later so various link_map fields are
set up that may be useful for note processing such as l_phdr.
The second pass should be before the fd is closed so that is
available.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>