UPSTREAM: staging/gdm72xx: use kzalloc for phydev and udev

UPSTREAM: staging/gdm72xx: use kzalloc for phydev and udev

we are doing kmalloc and memset, can be done using kzalloc itself.

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 7fc03add26e1e1f0b375e905547e01da6cdc1599)

Change-Id: I0afe8284b524dd28bd03fe26f24bccdb678fcfd3
Signed-off-by: Ben Chan <benchan@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/28218
Reviewed-by: Olof Johansson <olofj@chromium.org>