Add the inline function "is_power_of_2()" to log2.h, where the value
zero is *not* considered to be a power of two.
Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>