msm: vidc: Convert realloc to resource managed malloc to avoid memleak.

Whenever the probe is deferred, the resources that are allocated by
devm_kzalloc() will automatically get freed, but that are
allocated by krealloc() has to be freed explicitly.
In video driver currently memory related to regulator is allocated
using krealloc. Such memory is causing memory leak when probe is deferred.

Convert krealloc to devm_kzalloc to avoid memleak during probe defer.

Change-Id: I6653a6c204fb219a4a72e14904ff1c044a57b976
Signed-off-by: Manikanta Sivapala <msivap@codeaurora.org>