x86/kexec: Remove obsolete 'in_crash_kexec' flag

Previously, UV NMI used the 'in_crash_kexec' flag to determine whether
we are in a kdump kernel or not:

5edd19af18a36a4 ("x86, UV: Make kdump avoid stack dumps")

But this flags was removed in the following commit:

9c48f1c629ecfa1 ("x86, nmi: Wire up NMI handlers to new routines")

Since it isn't used any more, remove it.

Signed-off-by: Minfei Huang <[e-mail]>
Acked-by: Don Zickus <[e-mail]>
Cc: H. Peter Anvin <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

arch/x86/include/asm/kdebug.h

···
 extern void __show_regs(struct pt_regs *regs, int all);
 extern unsigned long oops_begin(void);
 extern void oops_end(unsigned long, struct pt_regs *, int signr);
-#ifdef CONFIG_KEXEC_CORE
-extern int in_crash_kexec;
-#else
-/* no crash dump is ever in progress if no crash kernel can be kexec'd */
-#define in_crash_kexec 0
-#endif
 
 #endif /* _ASM_X86_KDEBUG_H */

arch/x86/kernel/crash.c

···
 	unsigned int type;
 };
 
-int in_crash_kexec;
-
 /*
  * This is used to VMCLEAR all VMCSs loaded on the
  * processor. And when loading kvm_intel module, the
···
 
 static void kdump_nmi_shootdown_cpus(void)
 {
-	in_crash_kexec = 1;
 	nmi_shootdown_cpus(kdump_nmi_callback);
 
 	disable_local_APIC();