staging: greybus: remove redundant assignment to variable is_empty

The variable is_empty is being initialized with a value that is never
read and it is being updated later with a new value. The
initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Vaibhav Agarwal <vaibhav.sr@gmail.com>
Reviewed-by: Mark Greer <mgreer@animalcreek.com>
Link: https://lore.kernel.org/r/20190704133031.28809-1-colin.king@canonical.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>