libraw: bump version

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

package/libraw/libraw.mk

@@ -4,7 +4,7 @@
 #
 #############################################################
 
-LIBRAW_VERSION = 0.13.1
+LIBRAW_VERSION = 0.13.4
 LIBRAW_SOURCE = LibRaw-$(LIBRAW_VERSION).tar.gz
 LIBRAW_SITE = http://www.libraw.org/data/