Fix libsrtp.a dependency for apps without linking twice with it.
diff --git a/Makefile.in b/Makefile.in
index f30e260..0d232e1 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -66,7 +66,7 @@
 %.o: %.c
 	$(COMPILE) -c $< -o $@
 
-%$(EXE): %.c libsrtp.a 
+%$(EXE): %.c
 	$(COMPILE) $(LDFLAGS) $< -o $@ $(SRTPLIB) $(LIBS)
 
 
@@ -135,6 +135,8 @@
 testapp = $(crypto_testapp) test/srtp_driver$(EXE) test/replay_driver$(EXE) \
 	  test/roc_driver$(EXE) test/rdbx_driver$(EXE) test/rtpw$(EXE)
 
+$(testapp): libsrtp.a
+
 test/rtpw$(EXE): test/rtpw.c test/rtp.c
 	$(COMPILE) $(LDFLAGS) -o $@ $^ $(LIBS) $(SRTPLIB)