Switch GB SDK to 2.4 / API 10. Do not merge.

Change-Id: I8e3c97c5c281b05e2e03b6739221ea8b13536bd3
diff --git a/sdk/plat_tools_source.properties b/sdk/plat_tools_source.properties
index 9528e79..f23e52a 100644
--- a/sdk/plat_tools_source.properties
+++ b/sdk/plat_tools_source.properties
@@ -1,2 +1,2 @@
 Pkg.UserSrc=false
-Pkg.Revision=2
+Pkg.Revision=3