[myanmar] Handle U+AA74..U+AA76

Fixes https://github.com/behdad/harfbuzz/issues/218

src/hb-ot-shape-complex-myanmar.cc

diff --git a/src/hb-ot-shape-complex-myanmar.cc b/src/hb-ot-shape-complex-myanmar.cc
index 545765d..577d790 100644
--- a/src/hb-ot-shape-complex-myanmar.cc
+++ b/src/hb-ot-shape-complex-myanmar.cc
@@ -249,6 +249,11 @@
     case 0x104Au: case 0x104Bu:
       cat = (indic_category_t) OT_P;
       break;
+
+    case 0xAA74u: case 0xAA75u: case 0xAA76u:
+      /* https://github.com/roozbehp/unicode-data/issues/3 */
+      cat = (indic_category_t) OT_C;
+      break;
   }
 
   if (cat == OT_M)