linux-firmware: switch to http url

As recommended by Yegor Yefremov for f2fs-tools some firewalls might
restrict the git port and make life harder.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/linux-firmware/linux-firmware.mk

@@ -3,8 +3,9 @@
 # linux-firmware
 #
 #############################################################
+
 LINUX_FIRMWARE_VERSION = 65a5163b8bb77bd7759efa3ca780867fcaed89b0
-LINUX_FIRMWARE_SITE = git://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git
+LINUX_FIRMWARE_SITE = http://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git
 LINUX_FIRMWARE_SITE_METHOD = git
 
 # rt2501/rt61