For marking fused instructions clearly this patch adds a line before the
first instruction of pair and joins it with the arrow of the jump to its
target.

For example, when "je" is selected in annotate view, the line before
cmpl is displayed and joins the arrow of "je".

       │   ┌──cmpl   $0x0,argp_program_version_hook
 81.93 │   ├──je     20
       │   │  lock   cmpxchg %esi,0x38a9a4(%rip)
       │   │↓ jne    29
       │   │↓ jmp    43
 11.47 │20:└─→cmpxch %esi,0x38a999(%rip)

That means the cmpl+je is a fused instruction pair and they should be
considered together.

Changelog:

v3: Use Arnaldo's fix to improve the arrow origin rendering.  To get the
    evsel->evlist->env->cpuid, save the evsel in annotate_browser.

v2: new function "ins__is_fused" to check if the instructions are fused.
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1499403995-19857-3-git-send-email-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>