evm: Reset status even when security.evm is modified

hulk inclusion
category: feature
feature: IMA Digest Lists extension
bugzilla: 46797

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Without resetting the status when security.evm is modified, IMA appraisal
would continue to use the cached result and wouldn't detect whether the
meta_immutable requirement is still satisfied.

This patch calls evm_reset_status() in the post hooks when security.evm is
modified.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Tianxing Zhang <zhangtianxing3@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>