bus: ti-sysc: Increase max softreset wait

Otherwise we can get "OCP softreset timed out" warnings occasionally
at least for i2c2 on omap4 now that we check the OCP softreset completed
bit on enable.

Reported-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>