populate: fix installing dynamic linker 'ld.so'

The dynamic linker, ld.so, needs the execute bit to be set.
Detect tht the library being installed is in fact ld.so and
install it with 0755 instead of 0644.

Fix detecting src == dst.

Use a simpler command to copy src -> dst.

Also change echo to printf, get rid of 'echo -n', which is
highly non-portable.


-------- diffstat follows --------
/trunk/scripts/populate.in | 76 43 33 0 +++++++++++++++++++++++++++++-----------------------
1 file changed, 43 insertions(+), 33 deletions(-)
(transplanted from d7ddcb75e0f703e2ba6d17169167356389224870)

# x86_64 specific options

config ARCH_x86_64

    select ARCH_64

    select ARCH_SUPPORT_ARCH

    select ARCH_SUPPORT_CPU

    select ARCH_SUPPORT_TUNE

    help

      The x86_64 architecture, as defined by:

        http://www.amd.com/us-en/Processors/DevelopWithAMD/0,,30_2252_875_7044,00.html