AP_HAL: minlure: search for specific I2C controller

The number can change from one kernel version to another and even from
one boot to another. Find the I2C controller on sysfs and stick to that,
like it's done for PCA9685.

libraries/AP_HAL/board/linux.h

@@ -125,7 +125,7 @@
 #define HAL_INS_DEFAULT_ROTATION ROTATION_YAW_90
 #define HAL_INS_MPU60x0_NAME "mpu6000"
 #define HAL_BARO_DEFAULT HAL_BARO_MS5611_I2C
-#define HAL_BARO_MS5611_I2C_BUS 10
+#define HAL_BARO_MS5611_I2C_BUS { "platform/80860F41:06", }
 #define HAL_BARO_MS5611_I2C_ADDR 0x77
 /* Internal and external compasses */
 #define HAL_COMPASS_HMC5843_I2C_ADDR 0x1E