roseapplepi: add kernel patches to fix linux build issues with gcc 5

Backport 2 patches from upstream (from 3.18-rc1) for gcc 5.x support and a
patch from Marco Franceschetti (https://github.com/vonfritz/kernel/

) to fix
gcc 5.x compat issues in the bsp wifi drivers.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>