Move CMake variables for testing

Move the VENDER_NAME for GT.M to be out of the TEST_VISTA_FRESH If block.
Also move the TEST_VISTA_FRESH_SOURCE_DIR out of the same if block and put
it just before the Packages are globbed for the XINDEX tests.

Change-Id: I4bf7f8cd23a0ca45581b88d8d7a975e1f1a237de