configs/qemu: bump to the latest kernel version

configs/qemu: bump to the latest kernel version

Drop m68k-mcf5208 kernel patch since it's upstream.

Also bump the pc samples since they're tied to the (base) qemu config.

Results table:

Defconfig               Kernel  Qemu            Network Status
--------------------------------------------------------------
aarch64_virt            4.8.1   2.6.0           YES     OK (3)
arm_versatile           4.8.1   2.5.0           YES     OK
arm_vexpress            4.8.1   2.5.0           YES     OK
m68k_mcf5208            4.8.1   2.5.0           YES     OK
m68k_q800               4.8.1   q800-v2.4.0     NO (2)  OK
microblazebe            4.8.1   2.5.0           YES     OK
microblazeel            4.8.1   2.5.0           YES     OK
mips32r2el_malta        4.8.1   2.5.0           YES     OK
mips32r2_malta          4.8.1   2.5.0           YES     OK
mips32r6el_malta        4.8.1   2.6.0           YES     OK (3)
mips32r6_malta          4.8.1   2.6.0           YES     OK (3)
mips64el_malta          4.8.1   2.5.0           YES     OK
mips64_malta            4.8.1   2.5.0           YES     OK
mips64r6el_malta        4.8.1   2.7.0           YES     OK (3)(4)
mips64r6_malta          4.8.1   2.7.0           YES     OK (3)(4)
ppc_g3beige             4.8.1   2.5.0           YES     OK
ppc_mpc8544ds           4.8.1   2.5.0           YES     OK
ppc_virtex_ml507        4.8.1   2.5.0           NO      OK
ppc64_pseries           4.8.1   2.5.0           YES     OK
sh4                     4.8.1   2.5.0           YES     OK
sh4eb                   4.8.1   2.5.0           NO (1)  OK
sparc_ss10              4.8.1   2.5.0           YES     OK
sparc64_sun4u           4.8.1   2.5.0           YES     OK
sparc_sun4u             4.8.1   2.5.0           YES     OK
x86                     4.8.1   2.5.0           YES     OK
x86_64                  4.8.1   2.5.0           YES     OK
xtensa_lx60             4.8.1   2.6.0           YES     OK
xtensa_lx60_nommu       4.8.1   2.6.0           YES     OK

(1) - Probably an endian issue with 8139 emulation/driver
(2) - There's a network interface, but enabling it in qemu fails
(3) - Known to fail with qemu versions lower than 2.6.0
(4) - Might work with 2.6.0, but the cpu definition changed in 2.7.0

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>