staging: lustre: selftest.h: replace IS_PO2 by is_power_of_2

Replaces IS_PO2 by is_power_of_2. It is more accurate to use
is_power_of_2 since it returns 1 for numbers that are powers
of 2 only whereas IS_PO2 returns 1 for 0 and numbers that are
powers of 2.
Signed-off-by: Aya Mahfouz <mahfouz.saif.elyazal@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lnet/selftest/selftest.h

@@ -585,7 +585,7 @@ swi_state2str (int state)
 do {									\
 	int __I = 2;							\
 	while (!(cond)) {						\
-		CDEBUG(IS_PO2(++__I) ? D_WARNING : D_NET,		\
+		CDEBUG(is_power_of_2(++__I) ? D_WARNING : D_NET,	\
 		       fmt, ## __VA_ARGS__);				\
 		spin_unlock(&(lock));					\
 									\