target-i386: Move apic_state field from CPUX86State to X86CPU

This motion is preparing for refactoring vCPU APIC subsequently.

Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/cpus.c b/cpus.c
index 01d128d..ca4c59f 100644
--- a/cpus.c
+++ b/cpus.c
@@ -1458,12 +1458,11 @@
 
     CPU_FOREACH(cs) {
         X86CPU *cpu = X86_CPU(cs);
-        CPUX86State *env = &cpu->env;
 
-        if (!env->apic_state) {
+        if (!cpu->apic_state) {
             cpu_interrupt(cs, CPU_INTERRUPT_NMI);
         } else {
-            apic_deliver_nmi(env->apic_state);
+            apic_deliver_nmi(cpu->apic_state);
         }
     }
 #elif defined(TARGET_S390X)