mpu9250: create dedicated i2c version and delete legacy driver

- update crazyflie and bbblue usage
 - eventually this should be merged with the SPI version after interface
changes are made

posix-configs/bbblue/px4.config

@@ -51,7 +51,7 @@ load_mon start
 
 bmp280 -I start
 
-mpu9250 -I start
+mpu9250_i2c -I start
 # options:  -R rotation
 
 gps start -d /dev/ttyS2 -s -p ubx

posix-configs/bbblue/px4_fw.config

@@ -49,7 +49,7 @@ dataman start
 
 bmp280 -I start
 
-mpu9250 -I start
+mpu9250_i2c -I start
 # options:  -R rotation
 
 gps start -d /dev/ttyS2 -s -p ubx

posix-configs/eagle/flight/px4.config

@@ -7,7 +7,7 @@ gps start -d /dev/tty-4
 param set MAV_TYPE 2
 sleep 1
 hmc5883 start
-mpu9250 start_without_mag
+mpu9250 start
 bmp280 start
 sleep 1
 rc_update start