livepatch: __klp_disable_patch() should never be called for disabled patches

livepatch: __klp_disable_patch() should never be called for disabled patches

__klp_disable_patch() should never be called when the patch is not
enabled. Let's add the same warning that we have in __klp_enable_patch().

This allows to remove the check when calling klp_pre_unpatch_callback().
It was strange anyway because it repeatedly checked per-patch flag
for each patched object.

Signed-off-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>