mailbox: bcm-flexrm-mailbox: Fix mask used in CMPL_START_ADDR_VALUE()

The mask used in CMPL_START_ADDR_VALUE() should be 27bits instead of
26bits. This incorrect mask was causing completion writes to 40bits
physical address fail.

This patch fixes mask used in CMPL_START_ADDR_VALUE() macro.

Fixes: dbc049eee730 ("mailbox: Add driver for Broadcom FlexRM
ring manager")

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
diff --git a/drivers/mailbox/bcm-flexrm-mailbox.c b/drivers/mailbox/bcm-flexrm-mailbox.c
index a0be2ea..46ad305 100644
--- a/drivers/mailbox/bcm-flexrm-mailbox.c
+++ b/drivers/mailbox/bcm-flexrm-mailbox.c
@@ -97,7 +97,7 @@
 
 /* Register RING_CMPL_START_ADDR fields */
 #define CMPL_START_ADDR_VALUE(pa)			\
-	((u32)((((u64)(pa)) >> RING_CMPL_ALIGN_ORDER) & 0x03ffffff))
+	((u32)((((u64)(pa)) >> RING_CMPL_ALIGN_ORDER) & 0x07ffffff))
 
 /* Register RING_CONTROL fields */
 #define CONTROL_MASK_DISABLE_CONTROL			12