Fix OUT_DIR usage

OUT_DIR is not guaranteed to end with a /

Test: m -j test-art-host-run-test ART_TEST_RUN_TEST_NO_RELOCATE=true
Change-Id: Ic11f4be106b3c67eb22f442f7afaea92bcf46817
diff --git a/test/run-test b/test/run-test
index 7d3d813..1ac2857 100755
--- a/test/run-test
+++ b/test/run-test
@@ -80,7 +80,7 @@
 
 # ANDROID_HOST_OUT is not set in a build environment.
 if [ -z "$ANDROID_HOST_OUT" ]; then
-    export ANDROID_HOST_OUT=${OUT_DIR:-$ANDROID_BUILD_TOP/out/}host/linux-x86
+    export ANDROID_HOST_OUT=${OUT_DIR:-$ANDROID_BUILD_TOP/out}/host/linux-x86
 fi
 
 # If JACK_CLASSPATH is not set, assume it only contains core-libart.