package/qpid-proton: update mirror url

The current mirror now only has the version 0.40.0 available.

Older version of apache packages moved to the "archive.apache.org"
location.

Fixes: https://autobuild.buildroot.org/results/853/853c354b9bde4408e122046496fd3f0e7ffb0b55
Signed-off-by: Thomas Perale <thomas.perale@mind.be>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

package/qpid-proton/qpid-proton.mk

@@ -6,7 +6,7 @@
 
 QPID_PROTON_VERSION = 0.35.0
 QPID_PROTON_SITE = \
-	https://downloads.apache.org/qpid/proton/$(QPID_PROTON_VERSION)
+	https://archive.apache.org/dist/qpid/proton/$(QPID_PROTON_VERSION)
 QPID_PROTON_LICENSE = Apache-2.0
 QPID_PROTON_LICENSE_FILES = LICENSE.txt
 QPID_PROTON_CPE_ID_VENDOR = apache