[PATCH -next] irq/qcom-mpm: Fix build error without MAILBOX

[YueHaibing]

If MAILBOX is n, building fails:

drivers/irqchip/irq-qcom-mpm.o: In function `mpm_pd_power_off':
irq-qcom-mpm.c:(.text+0x174): undefined reference to `mbox_send_message'
irq-qcom-mpm.c:(.text+0x174): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `mbox_send_message'

Make QCOM_MPM depends on MAILBOX to fix this.

Fixes: a6199bb514d8 ("irqchip: Add Qualcomm MPM controller driver")
Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
---
 drivers/irqchip/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 680d2fcf2686..15edb9a6fcae 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -433,6 +433,7 @@ config QCOM_PDC
 config QCOM_MPM
 	tristate "QCOM MPM"
 	depends on ARCH_QCOM
+	depends on MAILBOX
 	select IRQ_DOMAIN_HIERARCHY
 	help
 	  MSM Power Manager driver to manage and configure wakeup
-- 
2.17.1