Kobject: kobject_uevent.c: Collapse unnecessary loop nesting (top_kobj)

Collapses a do..while() loop within an if() to a simple while() loop for 
simplicity and readability.

Signed-off-by: John Anthony Kazos Jr. <jakj@j-a-k-j.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>