libfdt: update from upstream dtc commit 142419e

commit 142419e "dtc/libfdt: sparse fixes", for u-boot's libfdt copy.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Cc: Jerry Van Baren <gvb.uboot@gmail.com>
diff --git a/lib/libfdt/fdt.c b/lib/libfdt/fdt.c
index 4157b21..387e354 100644
--- a/lib/libfdt/fdt.c
+++ b/lib/libfdt/fdt.c
@@ -96,7 +96,7 @@
 
 uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
 {
-	const uint32_t *tagp, *lenp;
+	const fdt32_t *tagp, *lenp;
 	uint32_t tag;
 	int offset = startoffset;
 	const char *p;