Add MinGW 4.8.0 rev2 to pkg-nodes

This change will replace MinGW 4.8.0 rev1 with MinGW 4.8.0 rev2.

Change-Id: I70bded2ea9b0a652d5f588c133b9a0efaead11bc
Reviewed-by: Matti Paaso <matti.paaso@digia.com>
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>