Fix the ARM Build on Tizen Common

BUG=https://crosswalk-project.org/jira/browse/XWALK-1673
Fix the ARM Build on Tizen Common.

Change-Id: I41422108a85077cde1ba81f42c592cba9e78462b
Signed-off-by: Stephen Clymans <stephen.clymans@open.eurogiciel.org>
Does the comment below also apply to `armv7l`, or does NaCl fail to build with it for a different reason?