Android: Extra search directory to find make on windows

See QTCREATORBUG-9297.
Make the Android packages on Windows host to find the correct make tool
under MinGW4.8 TC.

Change-Id: I2867682a853bbde4b8ce224f197f2d3cc06e858e
Reviewed-by: Tim Jenssen <tim.jenssen@digia.com>
Reviewed-by: Daniel Teske <daniel.teske@digia.com>