upstream: fdtget: Fix multiple arg bug and add test for it

There is a rather unfortunate bug in fdtget in that if multiple argument
sets are provided, it just repeats displaying the first set ones for
each set.

Fix this bug and add a test for it.

Acked-by: David Gibson <david@gibson.dropbear.id.au>

(pulled in from mailing list after ack)
BUG=chromium-os:23249
TEST=FEATURES=test sudo -E emerge dtc

Change-Id: If9f38673776f3e6c3e4e099411fd70426752f6ca
3 files changed