LU-16518 pcc: fix unused-but-set-variable warnings

LU-16518 pcc: fix unused-but-set-variable warnings

In several places, pcc_file is set but never used.
Clang doesn't like this, so discard this variable.

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: I7fde9d49bd6309335e6f9083ba588fc86d495b1c
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/58177
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Qian Yingjin <qian@ddn.com>
Reviewed-by: Max Wang <wamax@amazon.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>