Revert "apic: fix kvm build on UP without IOAPIC"

This reverts commit f9808b7f.
After commit 'kvm: switch to apic_set_eoi_write, apic_write'
the stubs are no longer needed as kvm does not look at apicdrivers anymore.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/include/asm/apic.h

@@ -417,12 +417,7 @@ extern struct apic *apic;
 	__aligned(sizeof(struct apic *))				\
 	__section(.apicdrivers) = { &sym1, &sym2 }
 
-#ifdef CONFIG_X86_LOCAL_APIC
 extern struct apic *__apicdrivers[], *__apicdrivers_end[];
-#else
-#define __apicdrivers ((struct apic **)NULL)
-#define __apicdrivers_end ((struct apic **)NULL)
-#endif
 
 /*
  * APIC functionality to boot other CPUs - only used on SMP: