x86/apic: Cleanup apic_printk()s

Use the new apic_pr_*() helpers and cleanup the apic_printk() maze.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Tested-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/all/20240802155440.589821068@linutronix.de