Rename quic::kMaxPacketSize to quic::kMaxOutgoingPacketSize

As part of cl/242197597, QUIC now has separate values for maximum incoming and outgoing packet sizes. This CL renames the constant to be clearer.

gfe-relnote: constant rename, no functional impact
PiperOrigin-RevId: 242708648
Change-Id: I3f440ba44b9c12394026116aaecdd2c166cc63b6
diff --git a/quic/core/quic_packet_reader.cc b/quic/core/quic_packet_reader.cc
index 3216013..f03aa6d 100644
--- a/quic/core/quic_packet_reader.cc
+++ b/quic/core/quic_packet_reader.cc
@@ -83,7 +83,7 @@
 #if MMSG_MORE_NO_ANDROID
   // Re-set the length fields in case recvmmsg has changed them.
   for (int i = 0; i < kNumPacketsPerReadMmsgCall; ++i) {
-    DCHECK_LE(kMaxPacketSize, packets_[i].iov.iov_len);
+    DCHECK_LE(kMaxOutgoingPacketSize, packets_[i].iov.iov_len);
     msghdr* hdr = &mmsg_hdr_[i].msg_hdr;
     hdr->msg_namelen = sizeof(sockaddr_storage);
     DCHECK_EQ(1, hdr->msg_iovlen);