OMAP4: HSI: fix missing CAWAKE caused by modem wakeup spam trace

Removed trace every time modem wakes-up OMAP (can be several times per second).
This trace is called under interrupt context (PRCM int) and causes delay
in CAWAKE tasklet processing.

Change-Id: I4c856b0ff0f1b90cfe9fd0938441558ba59132a7
Reported-by: Gilles Bourgeois <gilles.bourgeois@renesasmobile.com>
Signed-off-by: Djamil Elaidi <d-elaidi@ti.com>
OMAP4: HSI: Added API to allow HSI device registration

If HSI support is not needed, omap_hsi device shall not be registered
as it will force the muxing of usbb1_ulpitll_clk pad to hsi1_cawake, which is
not good.

omap_hsi device will now only be registered if explicitly requested using new
API omap_hsi_allow_registration().

Change-Id: I405a614f0421056e4c5a5fee8b98b1482b40b8da
Signed-off-by: Djamil Elaidi <d-elaidi@ti.com>
OMAP4: HSI: mux: use hwmod muxing framework