drivers: net: can: Add probe type ASYNC for qti-can

Add probe type as PROBE_PREFER_ASYNCHRONOUS for
qti-can driver to improve the boot time and
unblock other drivers probe for getting delayed.

Change-Id: I701c444f493828fe3fd63c5cc28207bdcb20d357
Signed-off-by: Sumeet Sahu <sumesahu@codeaurora.org>