jasper: fix license typo

Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/jasper/jasper.mk

@@ -10,6 +10,6 @@ JASPER_SOURCE = jasper-$(JASPER_VERSION).tar.bz2
 JASPER_INSTALL_STAGING = YES
 JASPER_DEPENDENCIES = jpeg
 JASPER_LICENSE = MIT
-JASPER_LICENSE_FILE = LICENSE
+JASPER_LICENSE_FILES = LICENSE
 
 $(eval $(autotools-package))