joystick: Fix pointer sequencing in Switch Pro Controller user IMU calibration. Prevent reading potentially stale memory. No functional changes.

src/joystick/hidapi/SDL_hidapi_switch.c

@@ -1113,16 +1113,20 @@ static bool LoadIMUCalibration(SDL_DriverSwitch_Context *ctx)
         // Check for user calibration data. If it's present and set, it'll override the factory settings
         readParams.unAddress = k_unSPIIMUUserScaleStartOffset;
         readParams.ucLength = k_unSPIIMUUserScaleLength;
-        if (WriteSubcommand(ctx, k_eSwitchSubcommandIDs_SPIFlashRead, (uint8_t *)&readParams, sizeof(readParams), &reply) && (pIMUScale[0] | pIMUScale[1] << 8) == 0xA1B2) {
-            pIMUScale = reply->spiReadData.rgucReadData;
+        if (WriteSubcommand(ctx, k_eSwitchSubcommandIDs_SPIFlashRead, (uint8_t *)&readParams, sizeof(readParams), &reply)) {
+            Uint8 *pUserIMUScale = reply->spiReadData.rgucReadData;
 
-            sAccelRawX = (pIMUScale[3] << 8) | pIMUScale[2];
-            sAccelRawY = (pIMUScale[5] << 8) | pIMUScale[4];
-            sAccelRawZ = (pIMUScale[7] << 8) | pIMUScale[6];
+            if ((pUserIMUScale[0] | (pUserIMUScale[1] << 8)) == 0xA1B2) {
+                pIMUScale = pUserIMUScale;
 
-            sGyroRawX = (pIMUScale[15] << 8) | pIMUScale[14];
-            sGyroRawY = (pIMUScale[17] << 8) | pIMUScale[16];
-            sGyroRawZ = (pIMUScale[19] << 8) | pIMUScale[18];
+                sAccelRawX = (pIMUScale[3] << 8) | pIMUScale[2];
+                sAccelRawY = (pIMUScale[5] << 8) | pIMUScale[4];
+                sAccelRawZ = (pIMUScale[7] << 8) | pIMUScale[6];
+
+                sGyroRawX = (pIMUScale[15] << 8) | pIMUScale[14];
+                sGyroRawY = (pIMUScale[17] << 8) | pIMUScale[16];
+                sGyroRawZ = (pIMUScale[19] << 8) | pIMUScale[18];
+            }
         }
 
         // Accelerometer scale