Adapt kernel structure to current Linux standards
[*] move common/ files into root path
[*] move modules/ files into drivers/staging/bcm21553
[*] refer build to new modules location

Commit: https://github.com/androidarmv6/android_kernel_samsung_bcm21553-common/commit/0515a9bffb39bfb938704b1af0002eada764be08