Add scripts/coccinelle/resource_size.cocci

This semantic patch replaces explicit computations
of resource size by a call to resource_size.

Signed-off-by: Nicolas Palix <npalix@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michal Marek <mmarek@suse.cz>