Let's move some logic from _DEFINE_MAIN_FUNCTION() and other places
in main-func.h into functions that we implement in main-func.c to
allow moving some included headers from the header to the .c file.
crypt_init_data_device() replaces the crypt_device struct with a
new allocation, losing the old one, which we get from crypt_init().
Use crypt_set_data_device() instead.
Enhance the test to cover this option too.
This adds support for dm integrity targets and an associated
/etc/integritytab file which is required as the dm integrity device
super block doesn't include all of the required metadata to bring up
the device correctly. See integritytab man page for details.
Daan De Meyer
Yu Watanabe
Luca Boccassi
Lennart Poettering
Tony Asleson