selftests/net: unix: fix unused variable compiler warning

stable inclusion
from stable-v6.6.5
commit a989f76f2218bf751664f7866bb30c754fc17393
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8N21P

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a989f76f2218bf751664f7866bb30c754fc17393



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[ Upstream commit 59fef379d453781f0dabfa1f1a1e86e78aee919a ]

Remove an unused variable.

    diag_uid.c:151:24:
    error: unused variable 'udr'
    [-Werror,-Wunused-variable]

Fixes: ac011361 ("af_unix: Add test for sock_diag and UDIAG_SHOW_UID.")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231124171645.1011043-4-willemdebruijn.kernel@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>