fs_statfs: Fix pushing unused/uninitialized 'spare' values
fs_statfs: Fix pushing unused/uninitialized 'spare' values

uv_statfs_t.spare is never initialized/used in Libuv, so it makes no sense to provide it to the user

zhaozg/luv,zhaozg/luv,luvit/luv,luvit/luv