Before we start removing omap3 legacy booting support, let's make n900
DT booting behave the same way for ir-rx51 as the legacy booting does.

For now, we need to pass pdata to the ir-rx51 driver. This means that
the n900 tree can move to using DT based booting without having to carry
all the legacy platform data with it when it gets dropped from the mainline
tree.

Note that the ir-rx51 driver is currently disabled because of the
dependency to !ARCH_MULTIPLATFORM. This will get sorted out later
with the help of drivers/pwm/pwm-omap-dmtimer.c. But first we need
to add chained IRQ support to dmtimer code to avoid introducing new
custom frameworks.

So let's just pass the necessary dmtimer functions to ir-rx51 so we
can get it working in the following patch.

Cc: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>