i2c: i801: Remove i801_set_block_buffer_mode

If FEATURE_BLOCK_BUFFER is set then bit SMBAUXCTL_E32B is supported
and there's no benefit in reading it back. Origin of this check
seems to be 14 yrs ago when people were not completely sure which
chip versions support the block buffer mode.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>