BSSGP_Emulation: Make L3 (SM/GMM) decoding a compile-time option

This allows us to build low-level tests that don't require all of L3.

Change-Id: I7ef7e93e2cd1d37e7e4a62947ca8dfde30d93b95
diff --git a/sgsn/gen_links.sh b/sgsn/gen_links.sh
index 541670d..578b454 100755
--- a/sgsn/gen_links.sh
+++ b/sgsn/gen_links.sh
@@ -85,7 +85,7 @@
 DIR=../library
 FILES="Misc_Helpers.ttcn General_Types.ttcn GSM_Types.ttcn GSM_RR_Types.ttcn Osmocom_Types.ttcn RLCMAC_Templates.ttcn RLCMAC_Types.ttcn RLCMAC_CSN1_Templates.ttcn RLCMAC_CSN1_Types.ttcn RLCMAC_EncDec.cc "
 FILES+="NS_Emulation.ttcn PCUIF_Types.ttcn NS_CodecPort.ttcn NS_CodecPort_CtrlFunct.ttcn NS_CodecPort_CtrlFunctDef.cc "
-FILES+="BSSGP_Emulation.ttcn Osmocom_Gb_Types.ttcn "
+FILES+="BSSGP_Emulation.ttcnpp Osmocom_Gb_Types.ttcn "
 FILES+="Osmocom_CTRL_Types.ttcn Osmocom_CTRL_Functions.ttcn Osmocom_CTRL_Adapter.ttcn "
 FILES+="Osmocom_VTY_Functions.ttcn "
 FILES+="LLC_Templates.ttcn L3_Templates.ttcn L3_Common.ttcn "