kobject: Reorder fields in 'struct kobject'

kobject: Reorder fields in 'struct kobject'

Group some variables based on their sizes to reduce hole and avoid padding.
On x86_64, this shrinks the size of 'struct kobject' from 256 to 244 bytes.

This structure is often included in some other structures. So these other
structures will also benefit from this 8 bytes saving.

This is especially nice for structure like 'cma_kobject' or 'class_dir'
that are now 256 bytes long. When they are kzalloc()'ed, 256 bytes are
allocated, instead of 512.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/6c7d1e3005dbec5483bdb9b7b60071175bf7bf70.1688811201.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>