arch-arm: Forward declare kvm_vcpu_init

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: I6fa5be48498d1a8f9c070e9ded11e8cadd4b89a1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47679
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
diff --git a/src/arch/arm/kvm/base_cpu.hh b/src/arch/arm/kvm/base_cpu.hh
index ec9e5ad..3b2beb3 100644
--- a/src/arch/arm/kvm/base_cpu.hh
+++ b/src/arch/arm/kvm/base_cpu.hh
@@ -44,6 +44,7 @@
 #include "dev/arm/base_gic.hh"
 
 struct kvm_reg_list;
+struct kvm_vcpu_init;
 
 namespace gem5
 {
@@ -111,7 +112,7 @@
      *
      * @param target CPU type to emulate
      */
-    void kvmArmVCpuInit(const struct kvm_vcpu_init &init);
+    void kvmArmVCpuInit(const kvm_vcpu_init &init);
 
   private:
     std::unique_ptr<kvm_reg_list> tryGetRegList(uint64_t nelem) const;