xhci: Add xhci_reset_halted_ep() helper function

[ Upstream commit d8ac9500

 ]

Create a separate helper function to issue reset endpont commands
to clear halted endpoints.

This is useful for cases where a halted endpoint is discovered while
completing another command, and the endpoint halt needs to be cleared
with a endpoint reset first.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210129130044.206855-16-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: a1575120

 ("xhci: Prevent infinite loop in transaction errors recovery for streams")
Signed-off-by: Sasha Levin <sashal@kernel.org>