fuzz: Link all targets once

src/test/fuzz/parse_univalue.cpp

@@ -12,13 +12,13 @@
 #include <limits>
 #include <string>
 
-void initialize()
+void initialize_parse_univalue()
 {
     static const ECCVerifyHandle verify_handle;
     SelectParams(CBaseChainParams::REGTEST);
 }
 
-void test_one_input(const std::vector<uint8_t>& buffer)
+FUZZ_TARGET_INIT(parse_univalue, initialize_parse_univalue)
 {
     const std::string random_string(buffer.begin(), buffer.end());
     bool valid = true;