MFV r268119:

4914 zfs on-disk bookmark structure should be named *_phys_t

illumos/illumos-gate@7802d7bf98dec568dadf72286893b1fe5abd8602

MFC after:	2 weeks
Small merges from OpenSolaris:

These have no effect on FreeBSD, in fact they are ifdef'ed,
but make easier future merges:

6699767 panic in spec_open()

6718877 crgetzoneid() use can cause problems when forking processes with
USDT providers in a non global zone

MFC after:	3 days