Increase the timeout for disabling an IP block to five milliseconds.
This is to handle the usb_host_fs idle latency, which takes almost
four milliseconds after a host controller reset.

This is the second of two patches needed to resolve the following
boot warning:

omap_hwmod: usb_host_fs: _wait_target_disable failed

Thanks to Sergei Shtylyov <sshtylyov@mvista.com> for finding
an unrelated hunk in a previous version of this patch.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Cc: Tero Kristo <t-kristo@ti.com>