LVM2 test breakage

[Mikulas Patocka]

Hi

The commit e879a0d9cb086c8e52ce6c04e5bfa63825a6213c breaks the test 
shell/lvcreate-large-raid.sh in the lvm2 testsuite.

The breakage is caused by removing the line "read_bio->bi_opf = op | 
do_sync;"

Mikulas