selftests/zram: Makefile fix

Do not override run_tests, The default rule will just run TEST_PROGS

Signed-off-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
diff --git a/tools/testing/selftests/zram/Makefile b/tools/testing/selftests/zram/Makefile
index ec45513..29d8034 100644
--- a/tools/testing/selftests/zram/Makefile
+++ b/tools/testing/selftests/zram/Makefile
@@ -5,8 +5,5 @@
 
 include ../lib.mk
 
-run_tests:
-	@/bin/bash ./zram.sh
-
 clean:
 	$(RM) err.log