common/rc: fix check for disabled kmemleak
With kernel commit
b353756b2b71 ("kmemleak: always register debugfs
file") that was merged to v4.19-rc3, the kmemleak debugfs knob
exists even if kmemleak is disabled, but returns EBUSY on write.
Suppress EBUSY errors in tests by disabling _check_kmemleak() calls
if the write to kmemleak knob failed on _init_kmemleak().
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>