tlv: avoid misaligned memory access

They cause unit test crashing on ARM platform.

refs: #4609

Change-Id: Ifdb0401529de48b5c08ebcf6938d80ba87ff883d
diff --git a/tests/tlv/test-routing-table-entry.cpp b/tests/tlv/test-routing-table-entry.cpp
index a58918e..deaad1c 100644
--- a/tests/tlv/test-routing-table-entry.cpp
+++ b/tests/tlv/test-routing-table-entry.cpp
@@ -32,15 +32,15 @@
 const uint8_t RoutingTableEntryWithNexthopsData[] =
 {
   // Header
-  0x91, 0x37,
+  0x91, 0x3b,
   // Destination
   0x8e, 0x09, 0x07, 0x07, 0x08, 0x05, 0x64, 0x65, 0x73, 0x74, 0x31,
   // Nexthop
-  0x8f, 0x14, 0x8d, 0x08, 0x6e, 0x65, 0x78, 0x74, 0x68, 0x6f, 0x70,
-  0x31, 0x86, 0x08, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0xfa, 0x3f,
+  0x8f, 0x16, 0x8d, 0x08, 0x6e, 0x65, 0x78, 0x74, 0x68, 0x6f, 0x70,
+  0x31, 0x86, 0x0a, 0x86, 0x08, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0xfa, 0x3f,
   // Nexthop
-  0x8f, 0x14, 0x8d, 0x08, 0x6e, 0x65, 0x78, 0x74, 0x68, 0x6f, 0x70,
-  0x32, 0x86, 0x08, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0xfa, 0x3f
+  0x8f, 0x16, 0x8d, 0x08, 0x6e, 0x65, 0x78, 0x74, 0x68, 0x6f, 0x70,
+  0x32, 0x86, 0x0a, 0x86, 0x08, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0xfa, 0x3f
 };
 
 const uint8_t RoutingTableEntryWithoutNexthopsData[] =