platform: msm_shared: Add support for detecting nand device

Add support to detect nand boot device required to set the kernel command
line androidboot.bootdevice

Change-Id: I4c0ad4c3baefad6ce03a08bc1abc696b01204962
diff --git a/platform/msm_shared/qpic_nand.c b/platform/msm_shared/qpic_nand.c
index 46c26c3..f21e032 100644
--- a/platform/msm_shared/qpic_nand.c
+++ b/platform/msm_shared/qpic_nand.c
@@ -36,6 +36,7 @@
 #include <sys/types.h>
 #include <platform.h>
 #include <platform/clock.h>
+#include <platform/iomap.h>
 
 static uint32_t nand_base;
 static struct ptable *flash_ptable;
@@ -1759,3 +1760,8 @@
 	dprintf(INFO, "flash_write_image: success\n");
 	return 0;
 }
+
+uint32_t nand_device_base()
+{
+	return nand_base;
+}