media: staging: media: atomisp: Fix oops by unbalanced clk enable/disable call

media: staging: media: atomisp: Fix oops by unbalanced clk enable/disable call

The common-clk core expects clk consumers to always call enable/disable
in a balanced manner. The atomisp driver does not call gmin_flisclk_ctrl()
in a balanced manner, so add a clock_on bool and skip redundant calls.

This fixes kernel oops like this one:

[   19.811613] gc0310_s_config S
[   19.811655] ------------[ cut here ]------------
[   19.811664] WARNING: CPU: 1 PID: 720 at drivers/clk/clk.c:594 clk_core_disabl
[   19.811666] Modules linked in: tpm_crb(+) snd_soc_sst_atom_hifi2_platform tpm
[   19.811744] CPU: 1 PID: 720 Comm: systemd-udevd Tainted: G         C OE   4.1
[   19.811746] Hardware name: Insyde T701/T701, BIOS BYT70A.YNCHENG.WIN.007 08/2
[   19.811749] task: ffff988df7ab2500 task.stack: ffffac1400474000
[   19.811752] RIP: 0010:clk_core_disable+0xc0/0x130
...
[   19.811775] Call Trace:
[   19.811783]  clk_core_disable_lock+0x1f/0x30
[   19.811788]  clk_disable+0x1f/0x30
[   19.811794]  gmin_flisclk_ctrl+0x87/0xf0
[   19.811801]  0xffffffffc0528512
[   19.811805]  0xffffffffc05295e2
[   19.811811]  ? acpi_device_wakeup_disable+0x50/0x60
[   19.811815]  ? acpi_dev_pm_attach+0x8e/0xd0
[   19.811818]  ? 0xffffffffc05294d0
[   19.811823]  i2c_device_probe+0x1cd/0x280
[   19.811828]  driver_probe_device+0x2ff/0x450

Fixes: "staging: atomisp: use clock framework for camera clocks"

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>