OMAP5: USB: hsusbtll_clkctrl has to be in hw_auto for USB to work

USB TLL clocks do not support 'explicit_en', only 'hw_auto'
control (R. Sricharan). cm_l3init_hsusbtll_clkctrl has to be
moved to the clk_modules_hw_auto_essential[] array in order
to make the clock work.

This fix is needed (but not sufficient) for USB EHCI operation
in U-Boot.

Signed-off-by: Lubomir Popov <lpopov@mm-sol.com>