Remove devtoolset sourcing from openssl provisioning on Ubuntu

This line is a leftover from RHEL script and needs to be removed on
Ubuntu.

Change-Id: I8fc8ab7cff808da997cb88a3cec4c65eaa1528a4
Reviewed-by: Heikki Halmet <heikki.halmet@qt.io>

coin/provisioning/qtci-linux-Ubuntu-16.04-x86_64/10-openssl_for_android_linux.sh

@@ -33,8 +33,6 @@
 ##
 #############################################################################
 
-source /opt/rh/devtoolset-4/enable
-
 set -ex
 
 source "${BASH_SOURCE%/*}/../common/openssl_for_android_linux.sh"