EHCI: fix port reset reporting

Commit b416191a (Fix EHCI port reset.) didn't
move the code that checked for successful clearing of the port reset bit from
ehci_submit_root(), relying on wait_ms() call instead. The mentioned code also
erroneously reported port reset state when the reset was already completed.

Signed-off-by: Sergei Shtylyov <sshtylyov@mvista.com>