ARM: OMAP2: Fix tusb6010 init error and compilation warning

Fix "tusb6010 init error 5, -19" and compilation warning from function
tusb6010_platform_retime "warning: 'sysclk_ps' is used uninitialized in this
function".

I suppose commit c094ba34b8f780885d029ce3c2715a194b780e5d was meant to test
for zero fclk_ps instead of sysclk_ps.

Signed-off-by: Jarkko Nikula <jarkko.nikula@nokia.com>
Cc: Roel Kluin <roel.kluin@gmail.com>
Tested-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: Tony Lindgren <tony@atomide.com>