fbdev: viafb: Make I2C terminology more inclusive

I2C v7, SMBus 3.2, and I3C 1.1.1 specifications have replaced "master/slave"
with more appropriate terms. Inspired by Wolfram's series to fix drivers/i2c/,
fix the terminology for users of I2C_ALGOBIT bitbanging interface, now that
the approved verbiage exists in the specification.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Signed-off-by: Helge Deller <deller@gmx.de>