Output a summary of optional SVM features in dmesg similar to CPU features.
If bootverbose is enabled, a detailed list is provided; otherwise, a
single-line summary is displayed.

Differential Revision:	https://reviews.freebsd.org/D1008
Reviewed by:	jhb, neel
MFC after:	1 week
Remove bhyve SVM feature printf's now that they are available in the
general CPU feature detection code.

Reviewed by:	neel
Some cxgbe/iw_cxgbe fixes:
- Free rt in c4iw_connect only if it is allocated.
- Call soclose instead of so_shutdown if there is an abort from the peer.
- Close socket and return failure if TOE is not enabled.

Submitted by:	Hariprasad at Chelsio dot com
Sponsored by:	Chelsio Communications