[media] exynos-gsc: fix s2r functionality

When gsc is in runtime suspended state, there is no need to call
m2m_suspend during suspend and similarly, there is no need to call
m2m_resume during resume if already in runtime suspended state. This
patch adds the necessary conditions to achieve this.

Signed-off-by: Prathyush K <prathyush.k@samsung.com>
Signed-off-by: Arun Mankuzhi <arun.m@samsung.com>
Signed-off-by: Arun Kumar K <arun.kk@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>