commit fae009d1 upstream.

Useless to count the register index in number of bytes we are writing.

Fixes a regression with hw i2c enabled.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>