Don't perform continuity check if there is no payload

According to ISO 13818-1: The continuity_counter shall not be incremented when the adaptation_field_control of the packet equals '00' or '10'.

src/dvbpsi.c

@@ -285,6 +285,10 @@ bool dvbpsi_packet_push(dvbpsi_t *p_dvbpsi, const uint8_t* p_data)
         return false;
     }
 
+    /* Return if no payload in the TS packet */
+    if (!(p_data[3] & 0x10))
+        return false;
+
     /* Continuity check */
     const bool b_first = (p_decoder->i_continuity_counter == DVBPSI_INVALID_CC);
     if (b_first)
@@ -329,10 +333,6 @@ bool dvbpsi_packet_push(dvbpsi_t *p_dvbpsi, const uint8_t* p_data)
 
     memcpy(p_decoder->prevpacket, p_data, 188);
 
-    /* Return if no payload in the TS packet */
-    if (!(p_data[3] & 0x10))
-        return false;
-
     /* Skip the adaptation_field if present */
     if (p_data[3] & 0x20)
         p_payload_pos = p_data + 5 + p_data[4];