- Use an explicit "depends_on module kernel" guard in DTrace libraries that

- Use an explicit "depends_on module kernel" guard in DTrace libraries that
  reference types defined in the kernel. Otherwise dtrace(1) expects to find
  CTF definitions for all referenced types, which is not very reasonable
  when it is being used in a build environment. This was previously worked
  around by adding "-x nolibs" to dtrace -h or -G invocations, but as of
  r283025, dtrace(1) actually handles dependencies properly, so this is no
  longer necessary.
- Remove "pragma ident" directives from DTrace libraries, as they're being
  phased out upstream as well.

Submitted by:	Krister Johansen <Krister.Johansen@isilon.com> [1]
MFC after:	1 week
Sponsored by:	EMC / Isilon Storage Division
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M    libdtrace/io.d
M    libdtrace/ip.d
M    libdtrace/nfs.d
M    libdtrace/nfssrv.d
M    libdtrace/psinfo.d
M    libdtrace/regs_x86.d
M    libdtrace/sched.d
M    libdtrace/siftr.d
M    libdtrace/tcp.d
M    libdtrace/udp.d