LIBVPX_TEST_DATA_PATH -> LIBAOM_TEST_DATA_PATH

This commit renames LIBVPX_TEST_DATA_PATH to LIBAOM_TEST_DATA_PATH,
with a work around for working with jenkins environmnet variables.

Change-Id: If664ce57e25ad2af8121d1b578bf64043f0baa2a
diff --git a/test/set_maps.sh b/test/set_maps.sh
index eada6d3..4f59b06 100755
--- a/test/set_maps.sh
+++ b/test/set_maps.sh
@@ -19,7 +19,7 @@
 # $LIBAOM_BIN_PATH.
 set_maps_verify_environment() {
   if [ ! -e "${YUV_RAW_INPUT}" ]; then
-    echo "Libaom test data must exist in LIBVPX_TEST_DATA_PATH."
+    echo "Libaom test data must exist in LIBAOM_TEST_DATA_PATH."
     return 1
   fi
   if [ -z "$(aom_tool_path set_maps)" ]; then