packet: remove empty and unused UDPVars struct

src/decode-udp.h

@@ -44,13 +44,9 @@ typedef struct UDPHdr_
 	uint16_t uh_sum;    /* checksum */
 } __attribute__((__packed__)) UDPHdr;
 
-typedef struct UDPVars_
-{
-} UDPVars;
-
-#define CLEAR_UDP_PACKET(p) do { \
-    (p)->udph = NULL; \
-    (p)->level4_comp_csum = -1; \
+#define CLEAR_UDP_PACKET(p) do {    \
+    (p)->level4_comp_csum = -1;     \
+    (p)->udph = NULL;               \
 } while (0)
 
 void DecodeUDPV4RegisterTests(void);

src/decode.h

@@ -467,12 +467,10 @@ typedef struct Packet_
     /* Can only be one of TCP, UDP, ICMP at any given time */
     union {
         TCPVars tcpvars;
-        UDPVars udpvars;
         ICMPV4Vars icmpv4vars;
         ICMPV6Vars icmpv6vars;
     } l4vars;
 #define tcpvars     l4vars.tcpvars
-#define udpvars     l4vars.udpvars
 #define icmpv4vars  l4vars.icmpv4vars
 #define icmpv6vars  l4vars.icmpv6vars