wlan-firmware: update to wlan-firmware-0.0.21

Signed-off-by: Stephan Raue <stephan@openelec.tv>
update nvidia driver to latest version
projects/RPi/patches/linux: update RPi support patch

Signed-off-by: Stephan Raue <stephan@openelec.tv>
Revert "projects/RPi/patches/linux: update RPi support patch"

This reverts commit c4ac5bccd32754e64dd510a88149938fc796a5f1.
config/version: set version to 4.0.3

Signed-off-by: Stephan Raue <stephan@openelec.tv>
config/version: set version back to devel

Signed-off-by: Stephan Raue <stephan@openelec.tv>