x86/apic: Remove unused inline function apic_set_eoi_cb()

Commit 2744a7ce ("x86/apic: Replace acpi_wake_cpu_handler_update() and
apic_set_eoi_cb()") left it unused.
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240803113704.246752-1-yuehaibing@huawei.com

arch/x86/include/asm/apic.h

@@ -489,7 +489,6 @@ static inline u64 apic_icr_read(void) { return 0; }
 static inline void apic_icr_write(u32 low, u32 high) { }
 static inline void apic_wait_icr_idle(void) { }
 static inline u32 safe_apic_wait_icr_idle(void) { return 0; }
-static inline void apic_set_eoi_cb(void (*eoi)(void)) {}
 static inline void apic_native_eoi(void) { WARN_ON_ONCE(1); }
 static inline void apic_setup_apic_calls(void) { }