media: atomisp: Remove atomisp_css_suspend()/_resume()

atomisp_css_suspend() is a 1:1 copy of atomisp_css_uninit() and
atomisp_css_resume() is a 1:1 copy of atomisp_css_init().

Remove the 2 copies and have their one caller just call
atomisp_css_uninit() / atomisp_css_init() instead.

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