iio: pressure: mprls0025pa improve driver error resilience

Improve driver error resilience by ignoring the measurement if any of
the 3 error flags gets set while interacting with the sensor.
Based on the datasheet, in table 14 on page 14, the status byte
contains:
    bit 5 busy flag - 1 if device is busy
    bit 2 memory integrity/error flag - 1 if integrity test failed
    bit 0 math saturation - 1 if internal math saturation has occurred
Co-developed-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Link: https://lore.kernel.org/r/20231229092445.30180-6-petre.rodan@subdimension.roSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/pressure/mprls0025pa.c

@@ -39,6 +39,8 @@
 #define MPR_I2C_MEMORY	BIT(2)	/* integrity test passed */
 #define MPR_I2C_MATH	BIT(0)	/* internal math saturation */
 
+#define MPR_I2C_ERR_FLAG  (MPR_I2C_BUSY | MPR_I2C_MEMORY | MPR_I2C_MATH)
+
 /*
  * support _RAW sysfs interface:
  *
@@ -213,7 +215,7 @@ static int mpr_read_pressure(struct mpr_data *data, s32 *press)
 					status);
 				return status;
 			}
-			if (!(status & MPR_I2C_BUSY))
+			if (!(status & MPR_I2C_ERR_FLAG))
 				break;
 		}
 		if (i == nloops) {
@@ -233,7 +235,7 @@ static int mpr_read_pressure(struct mpr_data *data, s32 *press)
 		return -EIO;
 	}
 
-	if (buf[0] & MPR_I2C_BUSY) {
+	if (buf[0] & MPR_I2C_ERR_FLAG) {
 		/*
 		 * it should never be the case that status still indicates
 		 * business