test: pci_ep: add basic pci_ep tests

Add basic PCI endpoint sandbox testing.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/include/asm/test.h b/arch/sandbox/include/asm/test.h
index e956a05..7ec9b61 100644
--- a/arch/sandbox/include/asm/test.h
+++ b/arch/sandbox/include/asm/test.h
@@ -177,4 +177,12 @@
  */
 int sandbox_get_pch_spi_protect(struct udevice *dev);
 
+/**
+ * sandbox_get_pci_ep_irq_count() - Get the PCI EP IRQ count
+ *
+ * @dev: Device to check
+ * @return irq count
+ */
+int sandbox_get_pci_ep_irq_count(struct udevice *dev);
+
 #endif