All functions prefixed with bdev_ are moved into bdev.c, and those
prefixed with cdev_ are now in cdev.c. The code in both files are
converted to KNF. The little (IOCTL-related) code left in device.c
is also cleaned up but should probably be moved into other existing
source files. This is left to a future patch. In general, VFS is
long overdue for a source code rebalancing, and the patch here is
only a step in the right direction.
Change-Id: I2fb25734b5778b44f2ff6d2ce331a8e2146e20b0
