net/tls: remove set but not used variables

Commit 4504ab0e6eb8 ("net/tls: Inform user space about send buffer availability")
made us report write_space regardless whether partial record
push was successful or not.  Remove the now unused return value
to clean up the following W=1 warning:

net/tls/tls_device.c: In function ‘tls_device_write_space’:
net/tls/tls_device.c:546:6: warning: variable ‘rc’ set but not used [-Wunused-but-set-variable]
  int rc = 0;
      ^~

CC: Vakul Garg <[email protected]>
CC: Boris Pismenny <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
Reviewed-by: Dirk van der Merwe <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
1 file changed