net: atm: Reduce the severity of logging in unlink_clip_vcc

In case of errors in unlink_clip_vcc, the logging level is set to
pr_crit but failures in clip_setentry are handled by pr_err().
The patch changes the severity consistent across invocations.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>