rampis: add support for status led on ASUS RT-N14U

The diag.sh script lacked an entry for the status led on the RT-N14U,
map it to the asus:blue:power led which is also used by the boot loader
to report boot status (eg. TFTP recovery mode VS normal boot)

Signed-off-by: Matteo Panella <m.panella@level28.org>

SVN-Revision: 45725