Fix Coverity Scan CID 300429 (Overrunning array buffer of 255 bytes by passing...

Fix Coverity Scan CID 300429 (Overrunning array buffer of 255 bytes by passing it to a function which accesses it at byte offset 65534 using argument size (which evaluates to 65535).)

openair2/RRC/LTE/rrc_eNB.c

@@ -8166,7 +8166,7 @@ rrc_eNB_generate_RRCConnectionReconfiguration_Sidelink(
 //-----------------------------------------------------------------------------
 {
   uint8_t                             buffer[RRC_BUF_SIZE];
-  uint16_t                            size = -1;
+  uint16_t                            size = 0;
   memset(buffer, 0, RRC_BUF_SIZE);
 
   // allocate dedicated pools for UE -sl-CommConfig/sl-DiscConfig (sl-V2X-ConfigDedicated)