ARM64: Enable shorten-64-to-32 warning

test/cctest/test-fuzz-arm64.cc

Index: test/cctest/test-fuzz-arm64.cc
diff --git a/test/cctest/test-fuzz-arm64.cc b/test/cctest/test-fuzz-arm64.cc
index ada609fe78af5ce345177f48dd03489f2aa1715f..8f6651a6a9554e929e1d6b76ede48ca52a274e1d 100644
--- a/test/cctest/test-fuzz-arm64.cc
+++ b/test/cctest/test-fuzz-arm64.cc
@@ -43,7 +43,7 @@ TEST(FUZZ_decoder) {
   Instruction buffer[kInstructionSize];
 
   for (int i = 0; i < instruction_count; i++) {
-    uint32_t instr = mrand48();
+    uint32_t instr = static_cast<uint32_t>(mrand48());
     buffer->SetInstructionBits(instr);
     decoder.Decode(buffer);
   }
@@ -64,7 +64,7 @@ TEST(FUZZ_disasm) {
 
   decoder.AppendVisitor(&disasm);
   for (int i = 0; i < instruction_count; i++) {
-    uint32_t instr = mrand48();
+    uint32_t instr = static_cast<uint32_t>(mrand48());
     buffer->SetInstructionBits(instr);
     decoder.Decode(buffer);
   }