zephyrjs-cli: Add more check for vid and pid
zephyrjs-cli: Add more check for vid and pid

Add more checks to make sure that given vid & pid are
non-empty numeric values.

Signed-off-by: Sudarsana Nagineni <467594e1763d28ab641517f34346d409bf4392f8@intel.com>

nagineni/zephyrjs-cli