missing system struct definitions during compilation files in /usr/lib/dtrace/ in local releng/10.1 build

[Ryan Stone]

dtrace gets the structure definitions from CTF debugging data in the
kernel image.  Did you use a custom kernel configuraton file?  Make
sure that you have these lines in your kernel config:

makeoptions     DEBUG=-g                # Build kernel with gdb(1) debug symbols
makeoptions     WITH_CTF=1              # Run ctfconvert(1) for DTrace support