Add Aghem (agq) and Masana (mcn)

Requested in Wikimedia Phabricator:
* https://phabricator.wikimedia.org/T293884
* https://phabricator.wikimedia.org/T288335

Aghem autonym according to Ethnologue. I can find several
variants online, and this looks like the most reliable.

Masana autonym according to
"Dictionnaire Masa-Français, Dialectes Gumay et Ɦaara (Tchad)"
by Melis Antonino

data/language-data.json

@@ -86,6 +86,13 @@
             ],
             "Afrikaans"
         ],
+        "agq": [
+            "Latn",
+            [
+                "AF"
+            ],
+            "aghɨ̂m"
+        ],
         "ahr": [
             "Deva",
             [
@@ -2413,6 +2420,13 @@
             ],
             "Basa Banyumasan"
         ],
+        "mcn": [
+            "Latn",
+            [
+                "AF"
+            ],
+            "vùn màsànà"
+        ],
         "mdf": [
             "Cyrl",
             [
@@ -4805,6 +4819,7 @@
             "bas",
             "ar",
             "ksf",
+            "agq",
             "ha-arab",
             "ha"
         ],