package: qemu: bump version to 2.8.0

This adds a CPU definition for the Cortex A7 along with improvements described
here: http://wiki.qemu-project.org/ChangeLog/2.8

Tested on an ARM Cortex A7 target (both target and host builds). The change log
does not describe any incompatible changes that would affect buildroot targets
as far as I am aware.

Signed-off-by: Andrey Yurovsky <yurovsky@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
(cherry picked from commit f56b13897b9f30c78d7ccd78a25b1e985179d2ab)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/qemu/qemu.hash

@@ -1,2 +1,2 @@
 # Locally computed, tarball verified with GPG signature
-sha256 326e739506ba690daf69fc17bd3913a6c313d9928d743bd8eddb82f403f81e53  qemu-2.7.0.tar.bz2
+sha256 dafd5d7f649907b6b617b822692f4c82e60cf29bc0fc58bc2036219b591e5e62  qemu-2.8.0.tar.bz2

package/qemu/qemu.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-QEMU_VERSION = 2.7.0
+QEMU_VERSION = 2.8.0
 QEMU_SOURCE = qemu-$(QEMU_VERSION).tar.bz2
 QEMU_SITE = http://wiki.qemu.org/download
 QEMU_LICENSE = GPLv2, LGPLv2.1, MIT, BSD-3c, BSD-2c, Others/BSD-1c