synergy: get rid of superfluous configure args and use sourceforge mirror

These are all provided by Makefile.autotools.in

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/synergy/synergy.mk

@@ -6,14 +6,11 @@
 
 SYNERGY_VERSION = 1.3.1
 SYNERGY_SOURCE = synergy-$(SYNERGY_VERSION).tar.gz
-SYNERGY_SITE = http://internap.dl.sourceforge.net/sourceforge/synergy2/
+SYNERGY_SITE = http://$(BR2_SOURCEFORGE_MIRROR).dl.sourceforge.net/sourceforge/synergy2/
 SYNERGY_AUTORECONF = NO
 SYNERGY_INSTALL_STAGING = NO
 SYNERGY_INSTALL_TARGET = YES
 
-SYNERGY_CONF_OPT = --target=$(GNU_TARGET_NAME) --host=$(GNU_TARGET_NAME) \
-		--build=$(GNU_HOST_NAME) --prefix=/usr --sysconfdir=/etc
-
 SYNERGY_DEPENDENCIES = xserver_xorg-server
 
 $(eval $(call AUTOTARGETS,package,synergy))