avahi: ensure locale data is installed into /usr/share, not /usr/lib v2

Was fixed in 0201ffcd1624, but nowadays avahi uses DATADIRNAME rather
than DATADIR.

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

package/avahi/avahi.mk

@@ -64,7 +64,7 @@ AVAHI_CONF_ENV = ac_cv_func_strtod=yes \
 		jm_cv_func_working_re_compile_pattern=yes \
 		ac_use_included_regex=no \
 		avahi_cv_sys_cxx_works=yes \
-		DATADIR=share
+		DATADIRNAME=share
 
 AVAHI_CONF_OPT = --localstatedir=/var \
 		--disable-qt3 \