ARM: OMAP2+: hsmmc.c: Remove dead code

Most platforms using OMAP hsmmc driver have switched to device tree
for passing platform data to omap_hsmmc.c driver.

The hsmmc.c file in mach-omap2 exists only to support pandora board
which uses wl1251 driver in legacy platform data mode.

Hence, remove the dead code not used by the pandora board.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>