FuzzerInitialize always exists

There was a time it could be NULL, but that was changed to always have it.
Reviewed-by: NRich Salz <rsalz@openssl.org>
GH: #2023

fuzz/driver.c

@@ -17,9 +17,7 @@
 
 int LLVMFuzzerInitialize(int *argc, char ***argv)
 {
-    if (FuzzerInitialize)
-        return FuzzerInitialize(argc, argv);
-    return 0;
+    return FuzzerInitialize(argc, argv);
 }
 
 int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len)
@@ -33,8 +31,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len)
 
 int main(int argc, char** argv)
 {
-    if (FuzzerInitialize)
-        FuzzerInitialize(&argc, &argv);
+    FuzzerInitialize(&argc, &argv);
 
     while (__AFL_LOOP(10000)) {
         uint8_t *buf = malloc(BUF_SIZE);