livepatch/core: Reuse common codes in the solution without ftrace

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8MGE6


CVE: NA

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There are some codes that can be used in the solution without ftrace,
such as module initialization and symbol relocation and so on, so
include them into CONFIG_LIVEPATCH.

Also note that CONFIG_LIVEPATCH_WO_FTRACE is still not implemented
in this patch.

Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>