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For Apple's arm64e or Linux's pauthtest, `Registers_arm64::link_reg_t` type is `__ptrauth`-qualified. When passing a value of such a type to a function accepting non-`__ptrauth`-qualified parameter with `pint_t` type, an authentication is performed. So, the corresponding callee argument does not contain an embedded signature, making it prone to substitution if spilled to the stack. This patch prevents early authentication of signed values of `link_reg_t` type by passing them as const l-value references instead of passing by value with type `pint_t`. This way, the callee would operate with a `__ptrauth`-qualified value containing a signature, allowing to detect a substitution if the value is spilled to the stack. Note that this approach was introduced previously in #143230 for some other functions. In this patch, we apply the approach to the functions which were not considered previously.
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