Remove duplicated WEBOS_INSTALL_LOGDIR variable

:Release Notes:
WEBOS_INSTALL_LOGDIR is no longer multiply defined

:Detailed Notes:
For some reason, WEBOS_INSTALL_LOGDIR was being initialized twice.
While this causes no problems at present, it may have been the 
source of a surprise at a later date if only the first instance was
modified.

:Testing Performed:

:QA Notes:

:Issues Addressed:

Open-webOS-DCO-1.0-Signed-off-by: Maksym Sditanov <maxim.sditanov@lge.com>

Change-Id: Ia04e31f32bdfc631985d183cd4ab8bea3fce0f48
Reviewed-on: https://g2g.palm.com/3832
Reviewed-by: Build Verification
Reviewed-by: Keith Derrick <keith.derrick@lge.com>
Tested-by: Keith Derrick <keith.derrick@lge.com>