qcacmn: Fix negative shift operand

Fix to avoid negative shift.

Change-Id: Idff0836e7e5ded0aeca400b057790df26c1c67fd
CRs-Fixed: 3609048

dp/wifi3.0/dp_internal.h

@@ -1465,6 +1465,8 @@ static inline int dp_log2_ceil(unsigned int value)
 	unsigned int tmp = value;
 	int log2 = -1;
 
+	if (qdf_unlikely(value == 0))
+		return 0;
 	while (tmp) {
 		log2++;
 		tmp >>= 1;