test-data.mk : Fix inadvertent use of LIBVPX instead of LIBAOM.

Change-Id: If02055bf288d2def45fb2fb2f0a447a41301ba04

test/test-data.mk

diff --git a/test/test-data.mk b/test/test-data.mk
index f0ce3ca..3943f6c 100644
--- a/test/test-data.mk
+++ b/test/test-data.mk
@@ -25,7 +25,7 @@
 
 ifeq ($(CONFIG_DECODE_PERF_TESTS),yes)
 # Encode / Decode test
-LIBVPX_TEST_DATA-$(CONFIG_AV1_ENCODER) += niklas_1280_720_30.yuv
+LIBAOM_TEST_DATA-$(CONFIG_AV1_ENCODER) += niklas_1280_720_30.yuv
 endif  # CONFIG_DECODE_PERF_TESTS
 
 ifeq ($(CONFIG_ENCODE_PERF_TESTS),yes)