[Ada] Minor typo fix in exp_unst.adb

2018-05-28  Arnaud Charlet  <charlet@adacore.com>

gcc/ada/

	* exp_unst.adb: Fix typo.

From-SVN: r260827

gcc/ada/ChangeLog

+2018-05-28  Arnaud Charlet  <charlet@adacore.com>
+
+	* exp_unst.adb: Fix typo.
+
 2018-05-28  Bob Duff  <duff@adacore.com>
 
 	* libgnat/a-convec.adb (Query_Element): Minor cleanup: remove an

gcc/ada/exp_unst.adb

@@ -1721,7 +1721,7 @@ package body Exp_Unst is
                   --  have to find the activation record needed by the
                   --  callee. This is as follows:
 
-                  --    ARECaF.ARECbU.ARECcU....ARECm
+                  --    ARECaF.ARECbU.ARECcU....ARECmU
 
                   --  where a,b,c .. m =
                   --    STF.Lev - 1,  STF.Lev - 2, STF.Lev - 3 .. STT.Lev