Check that boot loader config works in libs

tools/test/config/bootloader_missing/bootloaders/mbed_lib.json

@@ -0,0 +1,9 @@
+{
+    "name": "bl",
+    "target_overrides": {
+        "LPC1768": {
+            "target.bootloader_img": "does_not_exists.bin",
+            "target.restrict_size": "0xFFFFF"
+        }
+    }
+}

tools/test/config/bootloader_missing/mbed_app.json

@@ -1,7 +1,8 @@
 {
     "target_overrides": {
         "K64F": {
-            "target.bootloader_img": "does_not_exists.bin"
+            "target.bootloader_img": "does_not_exists.bin",
+            "target.restrict_size": "0xFFFFF"
         }
     }
 }

tools/test/config/bootloader_missing/test_data.json

@@ -1,5 +1,8 @@
 {
     "K64F": {
         "exception_msg": "not found"
+    },
+    "LPC1768": {
+        "exception_msg": "not found"
     }
 }