drm: give up on edid retries when i2c bus is not responding

This allows to avoid talking to a non-responding bus repeatedly until we
finally timeout after 15 attempts. We can do this by catching the -ENXIO
error, provided by i2c_algo_bit:bit_doAddress call.

Within the bit_doAddress we already try 3 times to get the edid data, so
if the routine tells us that bus is not responding, it is mostly pointless
to keep re-trying those attempts over and over again until we reach final
number of retries.

This change should fix https://bugs.freedesktop.org/show_bug.cgi?id=41059
and improve overall edid detection timing by 10-30% in most cases, and by
a much larger margin in case of phantom outputs (up to 30x in one worst
case).

Timing results for i915-powered machines for 'time xrandr' command:
Machine 1: from 0.840s to 0.290s
Machine 2: from 0.315s to 0.280s
Machine 3: from +/- 4s to 0.184s

Timing results for HD5770 with 'time xrandr' command:
Machine 4: from 3.210s to 1.060s

Reviewed-by: Chris Wilson <[email protected]>
Reviewed-by: Keith Packard <[email protected]>
Tested-by: Sean Finney <[email protected]>
Tested-by: Soren Hansen <[email protected]>
Tested-by: Hernando Torque <[email protected]>
Tested-by: Mike Lothian <[email protected]>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41059
Signed-off-by: Eugeni Dodonov <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>

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