drivers: ps/2: Tune PS2 driver to support severval mice brands

The PS/2 driver was enabled with a single mouse and kb brand.
However, when plugging other mice brands, the interaction between the
driver and the device(mouse) was broken. A delay after inhibithing
the PS/2 instance helped the internal FSM to start the TX process.

Signed-off-by: Francisco Munoz <francisco.munoz.ruiz@intel.com>