Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
* Align the 'Ok'/'FAILED!' test results in 'perf test.
* Support interrupted syscalls in 'trace'
* Add an event duration column and filter in 'trace'.
* There are references to the man pages in some tools, so try to build
Documentation when installing, warning the user if that is not possible,
from Borislav Petkov.
* Give user better message if precise is not supported, from David Ahern.
* Try to find cross-built objdump path by using the session environment
information in the perf.data file header, from Irina Tirdea, original
patch and idea by Namhyung Kim.
* Diplays more output on features check for make V=1, so that one can figure
out what is happening by looking at gcc output, etc. From Jiri Olsa.
* Account the nr_entries in rblist properly, fix by Suzuki K. Poulose.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>