media: atomisp: Move atomisp_streaming_count() check into __atomisp_css_recover()

Both callers of __atomisp_css_recover() check atomisp_streaming_count()
first, move the check into __atomisp_css_recover().

And __atomisp_css_recover() already calls lockdep_assert_held(&isp->mutex),
so drop that from atomisp_css_flush().

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>