Implement proper initialization of the different peripherals in
hardware_early_init() & hardware_init().  This includes stripping down
the display init so it does not perform a full reset anymore; we can do
this as the bootloader will have always performed the full reset
already.

Additionally this changeset enables the hardware_reset() function which
resets peripherals on load of a new app.  This should increase stability
as apps can always assume everything to be in its default state on load.

Signed-off-by: Rahix <rahix@rahix.de>