Add some missing function argument descriptions for 'ep', 'desc'
and 'zlp', and correct spelling/bitrot issues surrounding the
correct spelling of present args.

Fixes the following W=1 warnings:

 drivers/usb/cdns3/ep0.c:36: warning: Function parameter or member 'zlp' not described in 'cdns3_ep0_run_transfer'
 drivers/usb/cdns3/ep0.c:236: warning: Function parameter or member 'ctrl' not described in 'cdns3_req_ep0_get_status'
 drivers/usb/cdns3/ep0.c:236: warning: Excess function parameter 'ctrl_req' description in 'cdns3_req_ep0_get_status'
 drivers/usb/cdns3/ep0.c:411: warning: Function parameter or member 'ctrl' not described in 'cdns3_req_ep0_handle_feature'
 drivers/usb/cdns3/ep0.c:411: warning: Excess function parameter 'ctrl_req' description in 'cdns3_req_ep0_handle_feature'
 drivers/usb/cdns3/ep0.c:661: warning: Function parameter or member 'ep' not described in 'cdns3_gadget_ep0_enable'
 drivers/usb/cdns3/ep0.c:661: warning: Function parameter or member 'desc' not described in 'cdns3_gadget_ep0_enable'
 drivers/usb/cdns3/ep0.c:671: warning: Function parameter or member 'ep' not described in 'cdns3_gadget_ep0_disable'
 drivers/usb/cdns3/ep0.c:867: warning: Function parameter or member 'priv_ep' not described in 'cdns3_init_ep0'
 drivers/usb/cdns3/ep0.c:867: warning: Excess function parameter 'ep_priv' description in 'cdns3_init_ep0'

Cc: Pawel Laszczak <pawell@cadence.com>
Cc: Pawel Jez <pjez@cadence.com>
Cc: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200702144625.2533530-15-lee.jones@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>