LU-2675 libcfs: remove {linux,posix}-tracefile.h

LU-2675 libcfs: remove {linux,posix}-tracefile.h

Move the definition of the trace buffer type enum in
libcfs/libcfs/tracefile.h.  Remove the then unneeded headers
libcfs/libcfs/linux/linux-tracefile.h and
libcfs/libcfs/posix/posix-tracefile.h.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: Ied6fe04e98ba4d91197956ecf6566f73eabb7114
Reviewed-on: http://review.whamcloud.com/11983
Tested-by: Jenkins
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>