DBG: fixed a bug in DbgDisasmFastAt

Author: mrexodia

x64_dbg_dbg/_exports.cpp

@@ -739,6 +739,8 @@ extern "C" DLL_EXPORT uint _dbg_sendmessage(DBGMSG type, void* param1, void* par
         disasm.EIP = (UIntPtr)data;
         disasm.VirtualAddr = (UInt64)param1;
         int len = Disasm(&disasm);
+        if(len == UNKNOWN_OPCODE)
+            len = 1;
         uint i = 0;
         BASIC_INSTRUCTION_INFO* basicinfo = (BASIC_INSTRUCTION_INFO*)param2;
         fillbasicinfo(&disasm, basicinfo);