staging: sm750fb: ddk750_hwi2c: reduce amount of CamelCase

Rename camel case variables deviceAddress, pBuffer and totalBytes to
addr, buf and total_bytes respectively in sm750_hw_i2c_{read,write}_data
functions.

Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>