[diff.class] Fix typo "choise"

jwilk · jwilk · commit 8ebbcaebe13e · 2016-02-25T13:52:34.000+01:00
diff --git a/source/compatibility.tex b/source/compatibility.tex
@@ -668,7 +668,7 @@
 the implementation freedom was eliminated for non-dependent types,
 too.
 \effect
-The choise is implementation-defined in C, but not so in C++.
+The choice is implementation-defined in C, but not so in C++.
 \difficulty
 Syntactic transformation.
 \howwide
