LU-18141 quota: don't check for NULL before free'ing

LU-18141 quota: don't check for NULL before free'ing

The common free'ing macros already check for NULL,
so we don't need to explicitly check this beforehand.

The patch has been generated with the coccinelle script below.

@@
expression E;
@@
- if (E != NULL)
(
  OBD_FREE_PTR(E);
|
  OBD_FREE(E, ...);
|
  LIBCFS_FREE(E, ...);
|
  CFS_FREE_PTR(E);
|
  CFS_FREE_PTR_ARRAY(E, ...);
)

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: Ia32742483baa5fe5a4a26cc7a40cea107b211241
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/56034
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: jsimmons <jsimmons@infradead.org>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>