libosmo-rspro: Avoid useless dependency to libosmogsm

dpkg-shlibdeps: warning: package could avoid a useless dependency if debian/libosmo-rspro1/usr/lib/x86_64-linux-gnu/libosmo-rspro.so.1.0.0 was not linked against libosmogsm.so.13 (it uses none of the library's symbols)

Change-Id: I6ed59e4b1a23625653be2647f271a5d993535800
diff --git a/src/Makefile.am b/src/Makefile.am
index 6fff228..81fe4ca 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -16,7 +16,8 @@
 RSPRO_LIBVERSION=1:0:0
 lib_LTLIBRARIES = libosmo-rspro.la
 libosmo_rspro_la_LDFLAGS = $(AM_LDFLAGS) -version-info $(RSPRO_LIBVERSION)
-libosmo_rspro_la_LIBADD = $(OSMOCORE_LIBS) $(OSMOGSM_LIBS) $(OSMOABIS_LIBS) \
+# OSMOGSM_LIBS not needed, we don't use any of its symbols, only the header above
+libosmo_rspro_la_LIBADD = $(OSMOCORE_LIBS) $(OSMOABIS_LIBS) \
 			  rspro/libosmo-asn1-rspro.la
 libosmo_rspro_la_SOURCES = rspro_util.c asn1c_helpers.c