KVM: x86: Drop superfluous kvm_set_pic_irq() => kvm_pic_set_irq() wrapper

Drop the superfluous and confusing kvm_set_pic_irq() => kvm_pic_set_irq()
wrapper, and instead wire up ->set() directly to its final destination.

Opportunistically move the declaration kvm_pic_set_irq() to irq.h to
start gathering more of the in-kernel APIC/IO-APIC logic in irq.{c,h}.

No functional change intended.

Acked-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20250611213557.294358-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/include/asm/kvm_host.h

@@ -2209,7 +2209,6 @@ static inline int __kvm_irq_line_state(unsigned long *irq_state,
 	return !!(*irq_state);
 }
 
-int kvm_pic_set_irq(struct kvm_pic *pic, int irq, int irq_source_id, int level);
 void kvm_pic_clear_all(struct kvm_pic *pic, int irq_source_id);
 
 void kvm_inject_nmi(struct kvm_vcpu *vcpu);

arch/x86/kvm/i8259.c

@@ -185,8 +185,11 @@ void kvm_pic_update_irq(struct kvm_pic *s)
 	pic_unlock(s);
 }
 
-int kvm_pic_set_irq(struct kvm_pic *s, int irq, int irq_source_id, int level)
+int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		    int irq_source_id, int level, bool line_status)
 {
+	struct kvm_pic *s = kvm->arch.vpic;
+	int irq = e->irqchip.pin;
 	int ret, irq_level;
 
 	BUG_ON(irq < 0 || irq >= PIC_NUM_PINS);

arch/x86/kvm/irq.h

@@ -63,6 +63,8 @@ int kvm_pic_init(struct kvm *kvm);
 void kvm_pic_destroy(struct kvm *kvm);
 int kvm_pic_read_irq(struct kvm *kvm);
 void kvm_pic_update_irq(struct kvm_pic *s);
+int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		    int irq_source_id, int level, bool line_status);
 
 static inline int irqchip_split(struct kvm *kvm)
 {

arch/x86/kvm/irq_comm.c

@@ -27,14 +27,6 @@
 #include "x86.h"
 #include "xen.h"
 
-static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
-			   struct kvm *kvm, int irq_source_id, int level,
-			   bool line_status)
-{
-	struct kvm_pic *pic = kvm->arch.vpic;
-	return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
-}
-
 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
 			      struct kvm *kvm, int irq_source_id, int level,
 			      bool line_status)
@@ -296,7 +288,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
 		case KVM_IRQCHIP_PIC_MASTER:
 			if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2)
 				return -EINVAL;
-			e->set = kvm_set_pic_irq;
+			e->set = kvm_pic_set_irq;
 			break;
 		case KVM_IRQCHIP_IOAPIC:
 			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)