Typos

• "We are currently working on pur privacy policy" -> "our privacy policy" on https://www.rtems.org/privacy/
• "Rational" -> "Rationale" on https://docs.rtems.org/branches/master/user.html#rational
• "explcitly" in https://gitlab.rtems.org/rtems/docs/rtems-docs/-/blob/main/cpu-supplement/aarch64.rst?plain=1#L128