[gcompris] play_piano, english string typo.

[Bruno Coudoin <bcoudoin src gnome org>]

commit 954414d360e93d807a261bd2d84bb50f9e20b498
Author: GonÃalo Cordeiro <gzcordeiro gmail com>
Date:   Tue Oct 30 16:43:39 2012 +0100

    play_piano, english string typo.

 src/play_piano-activity/play_piano.xml.in |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/play_piano-activity/play_piano.xml.in b/src/play_piano-activity/play_piano.xml.in
index ad4cbfc..83dee71 100644
--- a/src/play_piano-activity/play_piano.xml.in
+++ b/src/play_piano-activity/play_piano.xml.in
@@ -27,8 +27,8 @@ The following keyboard bindings work in this game:
   - 3: E
   - 4: F
   - 5: G
-  - 6: E
-  - 7: F
+  - 6: A
+  - 7: B
   - 8: C (higher octave)
   - etc.
   - F1: C# / Db