ignore results of .ttcnpp files

Add another macro ignore_pp_results to gen_links.sh.inc and call from all
gen_links.sh files, to add results of *.ttcnpp files, i.e. generated *.ttcn
files, to .gitignore.

Change-Id: Ic7fb176226771212d7700dafaf27ac71f12a4a61
diff --git a/ggsn_tests/gen_links.sh b/ggsn_tests/gen_links.sh
index 25990d3..6ef52e1 100755
--- a/ggsn_tests/gen_links.sh
+++ b/ggsn_tests/gen_links.sh
@@ -44,3 +44,5 @@
 FILES="General_Types.ttcn GSM_Types.ttcn Osmocom_Types.ttcn Native_Functions.ttcn Native_FunctionDefs.cc IPCP_Types.ttcn "
 FILES+="GTP_CodecPort.ttcn GTP_CodecPort_CtrlFunct.ttcn GTP_CodecPort_CtrlFunctDef.cc GTP_Templates.ttcn "
 gen_links $DIR $FILES
+
+ignore_pp_results