libnih: Fix upstart crash on power-up

:Release Notes:
In a repeated on/off test, we saw about 2% of cycles resulted in an
assert crash in Upstart.  Adding this patch from Ubuntu fixes it

:Detailed Notes:
In power cycling tests, about 2% of power-ons resulted in an assert
crash in Upstart - giving this message:
init:com.ubuntu.Upstart.c:2651:
    Assertion failed in control_emit_event_emitted: env != NULL
Patch 4ubuntu16 for libnih resolves this issue.

:Testing Performed:
After a local build with this patch in place for libnih, I power-cycled
my TV 6117 times over the weekend and saw Zero crashes
miniBAT on vbuild 1475 attached to CCC GF-41045

:QA Notes:

:Issues Addressed:
[GF-40057] Crash on Upstart while repeated on/off test
[GF-41045] CCC: libnih=r2-4ubuntu16

Open-webOS-DCO-1.0-Signed-off-by: Ed Chejlava <ed.chejlava@lge.com>

Change-Id: I5925bf75b8496d077a69e98fb0e63f0b03a62514
Reviewed-on: https://g2g.palm.com/3603
Reviewed-by: Ed Chejlava <ed.chejlava@lge.com>
Tested-by: Ed Chejlava <ed.chejlava@lge.com>
Reviewed-by: Build Verification
Reviewed-by: Keith Derrick <keith.derrick@lge.com>
Reviewed-by: Jongho Kim <jongho1208.kim@lge.com>
Tested-by: Jongho Kim <jongho1208.kim@lge.com>