libfdt: Extend the reach of FDT_ERR_BADPHANDLE

So far, the BADPHANDLE error was only used for incorrect phandle values.
Extend that meaning to an improperly formatted phandle property.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

libfdt/libfdt.h

@@ -79,8 +79,10 @@
 	 * (e.g. missing a leading / for a function which requires an
 	 * absolute path) */
 #define FDT_ERR_BADPHANDLE	6
-	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
-	 * value.  phandle values of 0 and -1 are not permitted. */
+	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
+	 * This can be caused either by an invalid phandle property
+	 * length, or the phandle value was either 0 or -1, which are
+	 * not permitted. */
 #define FDT_ERR_BADSTATE	7
 	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
 	 * tree created by the sequential-write functions, which is