Sensors: remove the MPU3050 driver parent

Remove the MPU3040 gyroscope driver parent to allow the system
registers the driver in the "/sys/devices/virtual/input" folder.
The system will give the driver sysfs interface correct permission
according to the ueventd file.

CRs-Fixed: 510210
Change-Id: I957acc809005a06f6a8219140d8a4d609e46b435
Signed-off-by: Jie Cheng <rockiec@codeaurora.org>