x86/kvm: Remove defunct KVM_DEBUG_FS Kconfig

Remove KVM_DEBUG_FS, which can easily be misconstrued as controlling
KVM-as-a-host.  The sole user of CONFIG_KVM_DEBUG_FS was removed by
commit cfd8983f ("x86, locking/spinlocks: Remove ticket (spin)lock
implementation").
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200528031121.28904-1-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/Kconfig

@@ -821,14 +821,6 @@ config PVH
 	  This option enables the PVH entry point for guest virtual machines
 	  as specified in the x86/HVM direct boot ABI.
 
-config KVM_DEBUG_FS
-	bool "Enable debug information for KVM Guests in debugfs"
-	depends on KVM_GUEST && DEBUG_FS
-	---help---
-	  This option enables collection of various statistics for KVM guest.
-	  Statistics are displayed in debugfs filesystem. Enabling this option
-	  may incur significant overhead.
-
 config PARAVIRT_TIME_ACCOUNTING
 	bool "Paravirtual steal time accounting"
 	depends on PARAVIRT

arch/x86/kernel/kvm.c

@@ -21,7 +21,6 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/kprobes.h>
-#include <linux/debugfs.h>
 #include <linux/nmi.h>
 #include <linux/swait.h>
 #include <asm/timer.h>