i2c: add sanity check to i2c_put_adapter
i2c: add sanity check to i2c_put_adapter

i2c_put_adapter dereferences i2c_adapter pointer passed without check
for NULL. This adds a check for non-NULL pointer to allow i2c_put_adapter
called with NULL and behave the same way i2c_release_client does already.
It allows to simplify drivers where you need to release the adapter
during probe failures.

Signed-off-by: Sebastian Hesselbarth <1d402fe89ace836b52164ed4c0f247cb6f80efc1@gmail.com>
Signed-off-by: Wolfram Sang <fd4ce474653598159cad06f3c83387a05cd53a44@the-dreams.de>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs