fix compiler warning

src/include/switch_ivr.h

@@ -63,11 +63,11 @@ SWITCH_BEGIN_EXTERN_C struct switch_unicast_conninfo {
 typedef struct switch_unicast_conninfo switch_unicast_conninfo_t;
 
 #define SWITCH_IVR_VERIFY_SILENCE_DIVISOR(divisor) \
-	do { \
+	{ \
 		if ((divisor) <= 0 && (divisor) != -1) { \
 			divisor = 400; \
 		} \
-	} while(0);
+	}
 
 /**
  * @defgroup switch_ivr IVR Library