ANDROID: Revert "libfdt: Validate alias property value is a valid string."

This reverts commit 9308e7f9772bd226fea9925b1fc4d53c127ed4d5.

Revert the Android patch to apply the upstream fix [1] instead.

[1]: https://android.googlesource.com/platform/external/dtc/+/79b9e326a162b15ca5758ee214e350f4f7c038fe

Test: N/A
Change-Id: I702e619c875449b5efda529d01350117a1c4a435
diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c
index 362cc4a..e61df25 100644
--- a/libfdt/fdt_ro.c
+++ b/libfdt/fdt_ro.c
@@ -10,14 +10,6 @@
 
 #include "libfdt_internal.h"
 
-/* Check if a buffer contains a nul-terminated string.
- * Used for checking property values which should be strings.
- */
-static bool is_nul_string(const char *buf, const size_t buf_len) {
-	return buf_len > 0 && buf[buf_len - 1] == '\0' &&
-		strnlen(buf, buf_len) == buf_len - 1;
-}
-
 static int fdt_nodename_eq_(const void *fdt, int offset,
 			    const char *s, int len)
 {
@@ -536,27 +528,13 @@
 const char *fdt_get_alias_namelen(const void *fdt,
 				  const char *name, int namelen)
 {
-	const char *prop;
 	int aliasoffset;
-	int prop_len;
 
 	aliasoffset = fdt_path_offset(fdt, "/aliases");
 	if (aliasoffset < 0)
 		return NULL;
 
-	prop = fdt_getprop_namelen(fdt, aliasoffset, name, namelen, &prop_len);
-	if (prop && !can_assume(VALID_INPUT)) {
-		/* Validate the alias value.  From the devicetree spec v0.3:
-		 * "An alias value is a device path and is encoded as a string.
-		 *  The value representes the full path to a node, ..."
-		 * A full path must start at the root to prevent recursion.
-		 */
-		if (prop_len == 0 || *prop != '/' || !is_nul_string(prop, prop_len)) {
-			prop = NULL;
-		}
-	}
-
-	return prop;
+	return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
 }
 
 const char *fdt_get_alias(const void *fdt, const char *name)