livepatch: Fix compile warnning

hulk inclusion
category: bugfix
bugzilla: 181325 https://gitee.com/openeuler/kernel/issues/I4DDEL



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An error is reported during version building: error: ISO C90 forbids mixed
declarations and code.

Fix it by moving the variable definition forward.

Signed-off-by: Ye Weihua <yeweihua4@huawei.com>
Reviewed-by: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>