package/c-ares: use LICENSE.md

c-ares has a LICENSE.md file since version 1.12 and
https://github.com/c-ares/c-ares/commit/4e861351d9deaef7b78aee50ce9229325f4fc59a

So use it instead of one of the source file and add its hash

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/c-ares/c-ares.hash

@@ -1,2 +1,5 @@
 # Locally calculated after checking pgp signature
 sha256 45d3c1fd29263ceec2afc8ff9cd06d5f8f889636eb4e80ce3cc7f0eaf7aadc6e c-ares-1.14.0.tar.gz
+
+# Hash for license file
+sha256 db4eb63fe09daebdf57d3f79b091bb5ee5070c0d761040e83264e648d307af4c LICENSE.md

package/c-ares/c-ares.mk

@@ -11,7 +11,6 @@ C_ARES_CONF_OPTS = --with-random=/dev/urandom
 # Rebuild configure to avoid XC_CHECK_USER_CFLAGS
 C_ARES_AUTORECONF = YES
 C_ARES_LICENSE = MIT
-# No standalone, use some source file
-C_ARES_LICENSE_FILES = ares_mkquery.c
+C_ARES_LICENSE_FILES = LICENSE.md
 
 $(eval $(autotools-package))