xhci: dbc: Rename xhci_dbc_init and xhci_dbc_exit

xhci: dbc: Rename xhci_dbc_init and xhci_dbc_exit

These names give the impression the functions are related to
module init calls, but are in fact creating and removing the dbc
fake device

Rename them to xhci_create_dbc_dev() and xhci_remove_dbc_dev().

We will need the _init and _exit names for actual dbc module init
and exit calls.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>