ARM: OMAP2+: Remove __init from DSI mux functions

Commit d1589f09

 (ARM: OMAP2+: Mark
omap_hsmmc_init and omap_mux related functions as __init) changed DSI
muxing functions to __init. This doesn't work, as the muxing functions
are used every time a DSI display is enabled or disabled.

This patch removes the __inits from DSI mux functions that were
accidentally marked as __init, and makes omap4_hdmi_mux_pads __init
like it should be.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
[tony@atomide.com: update comments, mark omap4_hdmi_mux_pads __init]
Signed-off-by: Tony Lindgren <tony@atomide.com>