Move additional libraries to appropriate place

According to
https://www.gnu.org/software/automake/manual/automake.html#Libtool-Flags
the libraries supposed to be added to *_LDADD or *_LIBADD
while *_LDFLAGS should contain additional libtool linking
flags. Previously we used both. Let's unify this and move all the
libraries into proper automake variable. While at it - also add
libosmocore.la for tests to LDADD since all the tests link against it
anyway.

Change-Id: Ia657a66db75df831421af5df1175a992da5ba80f
diff --git a/src/sim/Makefile.am b/src/sim/Makefile.am
index 9590d6c..869e12d 100644
--- a/src/sim/Makefile.am
+++ b/src/sim/Makefile.am
@@ -5,7 +5,7 @@
 
 AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include -I$(top_builddir)/include
 AM_CFLAGS = -fPIC -Wall $(PCSC_CFLAGS) $(TALLOC_CFLAGS)
-AM_LDFLAGS = $(COVERAGE_LDFLAGS) $(TALLOC_LIBS)
+AM_LDFLAGS = $(COVERAGE_LDFLAGS)
 
 if ENABLE_PCSC
 # FIXME: only build the PC/SC dependent part conditional, but always build other parts