fix a memory leak.

This fixes a memory leak of pointer 'ascii_out'

BUG: None
Test: The warning is gone.
Change-Id: If3caa4c38dc9df377f1c06abb1ed9c963c9b353d
diff --git a/tests/vehicle/vehicle-hal-tool.c b/tests/vehicle/vehicle-hal-tool.c
index c93790a..e85df62 100755
--- a/tests/vehicle/vehicle-hal-tool.c
+++ b/tests/vehicle/vehicle-hal-tool.c
@@ -98,6 +98,7 @@
             memcpy(ascii_out, data->value.str_value.data, data->value.str_value.len);
             ascii_out[data->value.str_value.len] = '\0';
             printf("Value Type: STRING %s\n", ascii_out);
+            free(ascii_out);
             break;
         case VEHICLE_VALUE_TYPE_BYTES:
             printf("Value type: BYTES\n Size: %d", data->value.bytes_value.len);