Reset cpu data page offset when page is not mapped
Reset cpu data page offset when page is not mapped

When we reach the end of the data file and unmap the page, we
must also reset the page offset, otherwise the tracecmd_read_at
gets confused, and may think that a page can be mapped when it is
not.

Signed-off-by: Steven Rostedt <43232e92d70cc7aa53504ad0397085ee47bad87f@goodmis.org>

bigzz/trace-cmd,bigzz/trace-cmd