i2c: normal_i2c can be made const (remaining drivers)

Documentation/i2c/writing-clients

arch/arm/mach-pxa/akita-ioexp.c

drivers/i2c/chips/eeprom.c

drivers/i2c/chips/max6875.c

drivers/i2c/chips/pcf8574.c

drivers/i2c/chips/pcf8575.c

drivers/i2c/chips/pcf8591.c

drivers/macintosh/therm_windtunnel.c

drivers/usb/host/ohci-pnx4008.c

drivers/video/matrox/matroxfb_maven.c

drivers/w1/masters/ds2482.c

sound/soc/codecs/cs4270.c

sound/soc/s3c24xx/neo1973_wm8753.c