p2p: change CInv::type from int to uint32_t

fixes issue bitcoin#19678 UBSan implicit-integer-sign-change

Credit to Eugene (Crypt-iQ) for finding and reporting the issue
and to Vasil Dimov (vasild) for the original suggestion

Author: jonatack

src/protocol.cpp

@@ -163,7 +163,7 @@ CInv::CInv()
     hash.SetNull();
 }
 
-CInv::CInv(int typeIn, const uint256& hashIn) : type(typeIn), hash(hashIn) {}
+CInv::CInv(uint32_t typeIn, const uint256& hashIn) : type(typeIn), hash(hashIn) {}
 
 bool operator<(const CInv& a, const CInv& b)
 {

src/protocol.h

@@ -408,7 +408,7 @@ class CInv
 {
 public:
     CInv();
-    CInv(int typeIn, const uint256& hashIn);
+    CInv(uint32_t typeIn, const uint256& hashIn);
 
     SERIALIZE_METHODS(CInv, obj) { READWRITE(obj.type, obj.hash); }
 
@@ -425,7 +425,7 @@ class CInv
     // Combined-message helper methods
     bool IsGenTxMsg()     const { return type == MSG_TX || type == MSG_WTX || type == MSG_WITNESS_TX; }
 
-    int type;
+    uint32_t type;
     uint256 hash;
 };