i2c: npcm7xx: Group bank 0/1 registers together for readability

The unlabelled registers NPCM_I2CCTL4 to NPCM_I2CSCLHT overlap with the
bank 1 registers below, and they are accessed after selecting bank 0, so
they clearly belong to bank 0.

Move them together with the other bank 0 registers, and move the
unrelated definition of npcm_i2caddr down to keep the banked registers
in one piece.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>