bhnd(4): Fix bcma/siba core reset behavior

bhnd(4): Fix bcma/siba core reset behavior

Add missing support for specifying I/O control flags during core reset,
and resolve a number of siba(4)-specific reset issues:

- Add missing check for target reject flags in siba_is_hw_suspended().
- Remove incorrect wait on SIBA_TMH_BUSY when modifying any target state
  register; this should only be done when waiting for initiated
  transactions to clear.
- Add missing wait on SIBA_IM_BY when asserting SIBA_IM_RJ.
- Overwrite any previously set SIBA_TML_REJ flag when bringing the core
  out of reset. This fixes a lockup that occured when we brought up a core
  (after reboot) that had previously been placed into RESET by siba_bwn(4).

Approved by:	adrian (mentor, implicit)
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D13039