keymile, common; fix i2c deblocking support

This patch fix the i2c deblocking facility with the i2c HW-Controller.
The required delays for byte reading, the enhanced criteria for stop
the dummy read and required 5 start/stop sequences are added.

Add i2c deblocking before ivm eeprom read.

Improve i2c deblocking sequence by respecting stop hold time.

Cleaned function for deblocking. Have now one function i2c_make_abort()
available for bitbang, mpc82xx and mpc83xx harware controller.

Signed-off-by: Stefan Bigler <stefan.bigler@keymile.com>
Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Heiko Schocher <hs@denx.de>
cc: Valentin Longchamp <valentin.longchamp@keymile.com>