IPA_Emulation: Make dependencies to RSL/MGCP/SCCP/GSUP conditional

Let's use the preprocessor to avoid IPA_Emulation pulling *all*
dependencies into each and any of our projects.  The code readability
suffers a bit from the many #ifdefs, but compilation speed increases
if we don't have to pull in all those (recursive) dependencies.

After all, a BTS test case will never need SCCP, GSUP or MGCP.

Change-Id: Ic0231adbd2171214de133d26b3fbf36130ee8aa0
diff --git a/bsc-nat/regen_makefile.sh b/bsc-nat/regen_makefile.sh
index a3c6243..3d17cfe 100755
--- a/bsc-nat/regen_makefile.sh
+++ b/bsc-nat/regen_makefile.sh
@@ -2,6 +2,8 @@
 
 MAIN=IPA_Test.ttcn
 
-FILES="*.ttcn SCCP_EncDec.cc IPA_CodecPort_CtrlFunctDef.cc IPL4asp_PT.cc IPL4asp_discovery.cc TCCConversion.cc TCCInterface.cc RTP_EncDec.cc SDP_EncDec.cc *.c MGCP_CodecPort_CtrlFunctDef.cc"
+FILES="*.ttcn *.ttcnpp SCCP_EncDec.cc IPA_CodecPort_CtrlFunctDef.cc IPL4asp_PT.cc IPL4asp_discovery.cc TCCConversion.cc TCCInterface.cc RTP_EncDec.cc SDP_EncDec.cc *.c MGCP_CodecPort_CtrlFunctDef.cc"
+
+export CPPFLAGS_TTCN3="-DIPA_EMULATION_SCCP -DIPA_EMULATION_MGCP"
 
 ../regen-makefile.sh $MAIN $FILES