linux-yocto-rt/54: fix 5.4-rt build breakage

linux-yocto-rt/54: fix 5.4-rt build breakage

Integrating the following commit:

    commit 8d8179549a233e7517523ac12887016451da2e20
    Author: Bruce Ashfield <bruce.ashfield@gmail.com>
    Date:   Tue Jun 27 10:13:01 2023 -0400

        rt: fix 5.4-stable introduced compile errors

        The 5.4 stable series brough back two elements removed
        by the -rt patch:

         - tick_period
         - deferred/safe printk

        We fix the build by dropping the use of the period and
        deferred printk

Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>