This does the following:
 - remove trailing spaces
 - make loop.h independent by including bio.h, blk.h, spinlock.h
 - replace the lock/unlock functions by module_get/module_put;
   in struct loop this is the change
	-       void (*lock)(struct loop_device *);
	-       void (*unlock)(struct loop_device *);
	+       struct module *owner;
 - replace the integer lo_encrypt_type by the pointer lo_encryption;
   there was a race with loop_unregister_transfer
 - fixed an off-by-one in loop_register_transfer

This is Step 1 of a series of half a dozen or so.

Half of the above is from Jari. Anything that is wrong is mine.