msm: smd: add sanity check on platform resources

Add null sanity checks to fix corner cases.

Change-Id: Ic91ca37d74621ad414d23d8756881ee866250745
Signed-off-by: Brent Hronik <bhronik@codeaurora.org>
diff --git a/arch/arm/mach-msm/smd.c b/arch/arm/mach-msm/smd.c
index c97ba68..a6e3497 100644
--- a/arch/arm/mach-msm/smd.c
+++ b/arch/arm/mach-msm/smd.c
@@ -3382,8 +3382,9 @@
 	parent_pdev = to_platform_device(pdev->dev.parent);
 
 	key = "irq-reg-base";
-	/* existance check verified in smem driver */
 	r = platform_get_resource_byname(parent_pdev, IORESOURCE_MEM, key);
+	if (!r)
+		goto missing_key;
 	irq_out_size = resource_size(r);
 	irq_out_base = ioremap_nocache(r->start, irq_out_size);
 	if (!irq_out_base) {
@@ -3477,8 +3478,9 @@
 	parent_pdev = to_platform_device(pdev->dev.parent);
 
 	key = "irq-reg-base";
-	/* existance check verified in smem driver */
 	r = platform_get_resource_byname(parent_pdev, IORESOURCE_MEM, key);
+	if (!r)
+		goto missing_key;
 	irq_out_size = resource_size(r);
 	irq_out_base = ioremap_nocache(r->start, irq_out_size);
 	if (!irq_out_base) {