USB: msm_otg: Add proper check for used delay

Add aca_enabled check before used delay which was added to
overcome spurious interrupt when used with PET device. Removing
this delay would improve USB enumeration time when host supports
CDP port.

Change-Id: I8afbd068c8c27ef09f7ec8df7a347e83867a0117
Signed-off-by: Mayank Rana <mrana@codeaurora.org>