oe-time-dd-test.sh: provide more information from "top"

Improvements:
    - increase width to 512
    - pass -c option to show full command-line

Signed-off-by: Sakib Sajal <sakib.sajal@windriver.com>
Signed-off-by: Randy MacLeod <Randy.MacLeod@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>