docs: fix a few simple typos

[akshayaurora]

There are small typos in:

• plyer/facades/accelerometer.py
• plyer/facades/brightness.py
• plyer/facades/sms.py
• plyer/facades/wifi.py
• plyer/platforms/ios/camera.py
• plyer/platforms/ios/filechooser.py
• plyer/platforms/ios/sms.py
• plyer/platforms/ios/vibrator.py

Fixes:

• Should read specified rather than secified.
• Should read selection rather than seletion.
• Should read repetition rather than repeatition.
• Should read receiver rather than reveiver.
• Should read message rather than mesage.
• Should read chosen rather than choosen.
• Should read brightness rather than brightnesss.
• Should read accelerometer rather than acceletometer.

Closes #622