linux: update Radeon firmwares

Signed-off-by: Stephan Raue <stephan@openelec.tv>
gettext: update to gettext-0.19.1

Signed-off-by: Stephan Raue <stephan@openelec.tv>
file: update to file-5.19

Signed-off-by: Stephan Raue <stephan@openelec.tv>
libpng: update to libpng-1.6.12

Signed-off-by: Stephan Raue <stephan@openelec.tv>
dbus: update to dbus-1.8.4

Signed-off-by: Stephan Raue <stephan@openelec.tv>
libusb: update to libusb-1.0.19

Signed-off-by: Stephan Raue <stephan@openelec.tv>
gcc: add patches to fix GCC-60902, this should fix #3323

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