i2c_posix: fix simulate variable cannot be assigned on QuRT

src/drivers/device/i2c_posix.cpp

@@ -49,9 +49,15 @@
 #include <fcntl.h>
 #include <sys/ioctl.h>
 
+#ifdef __PX4_QURT
+#define PX4_SIMULATE_I2C 1
+#else
 #define PX4_SIMULATE_I2C 0
+#endif
+
 static constexpr const int simulate = PX4_SIMULATE_I2C;
 
+
 namespace device
 {
 
@@ -104,10 +110,6 @@ I2C::init()
 		return ret;
 	}
 
-#ifdef __PX4_QURT
-	simulate = true;
-#endif
-
 	if (simulate) {
 		_fd = 10000;