cyrus-sasl / postfix: work around recursive dependency issue in toolchain

Signed-off-by: Steven Barth <steven@midlink.org>

libs/cyrus-sasl/Makefile

@@ -32,7 +32,7 @@ define Package/libsasl2
   CATEGORY:=Libraries
   TITLE:=A general purpose authentication library
   URL:=http://asg.web.cmu.edu/sasl/
-  DEPENDS:=libopenssl
+  DEPENDS:=+libopenssl
 endef
 
 TARGET_CFLAGS += $(FPIC)