Convert CONFIG_CMD_IRQ to Kconfig

This converts the following to Kconfig:
   CONFIG_CMD_IRQ

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/PATI_defconfig b/configs/PATI_defconfig
index 0560866..cd78de7 100644
--- a/configs/PATI_defconfig
+++ b/configs/PATI_defconfig
@@ -21,6 +21,7 @@
 # CONFIG_CMD_NET is not set
 # CONFIG_CMD_NFS is not set
 CONFIG_CMD_BSP=y
+CONFIG_CMD_IRQ=y
 # CONFIG_MMC is not set
 CONFIG_MTD_NOR_FLASH=y
 # CONFIG_PCI is not set