Input: mma8450 - silence some 'uninitialized variable' warnings

Sometimes GCC is not smart enough to recognize that x, y and z are
always used properly initialized in mma8450_poll(). Let's rearrange
the code a bit to help GCC.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/misc/mma8450.c

@@ -88,13 +88,13 @@ static int mma8450_write(struct mma8450 *m, unsigned off, u8 v)
 	return 0;
 }
 
-static int mma8450_read_xyz(struct mma8450 *m, int *x, int *y, int *z)
+static int mma8450_read_block(struct mma8450 *m, unsigned off,
+			      u8 *buf, size_t size)
 {
 	struct i2c_client *c = m->client;
-	u8 buff[6];
 	int err;
 
-	err = i2c_smbus_read_i2c_block_data(c, MMA8450_OUT_X_LSB, 6, buff);
+	err = i2c_smbus_read_i2c_block_data(c, off, size, buf);
 	if (err < 0) {
 		dev_err(&c->dev,
 			"failed to read block data at 0x%02x, error %d\n",
@@ -102,10 +102,6 @@ static int mma8450_read_xyz(struct mma8450 *m, int *x, int *y, int *z)
 		return err;
 	}
 
-	*x = ((buff[1] << 4) & 0xff0) | (buff[0] & 0xf);
-	*y = ((buff[3] << 4) & 0xff0) | (buff[2] & 0xf);
-	*z = ((buff[5] << 4) & 0xff0) | (buff[4] & 0xf);
-
 	return 0;
 }
 
@@ -114,7 +110,7 @@ static void mma8450_poll(struct input_polled_dev *dev)
 	struct mma8450 *m = dev->private;
 	int x, y, z;
 	int ret;
-	int err;
+	u8 buf[6];
 
 	ret = mma8450_read(m, MMA8450_STATUS);
 	if (ret < 0)
@@ -123,10 +119,14 @@ static void mma8450_poll(struct input_polled_dev *dev)
 	if (!(ret & MMA8450_STATUS_ZXYDR))
 		return;
 
-	err = mma8450_read_xyz(m, &x, &y, &z);
-	if (err)
+	ret = mma8450_read_block(m, MMA8450_OUT_X_LSB, buf, sizeof(buf));
+	if (ret < 0)
 		return;
 
+	x = ((buf[1] << 4) & 0xff0) | (buf[0] & 0xf);
+	y = ((buf[3] << 4) & 0xff0) | (buf[2] & 0xf);
+	z = ((buf[5] << 4) & 0xff0) | (buf[4] & 0xf);
+
 	input_report_abs(dev->input, ABS_X, x);
 	input_report_abs(dev->input, ABS_Y, y);
 	input_report_abs(dev->input, ABS_Z, z);