media: bcm2835-unicam: Depend on COMMON_CLK

The bcm2835-unicam driver calls the clk_set_min_rate() function, which
is declared but not implemented on platforms that don't provide
COMMON_CLK. This causes linkage failures with some configurations.

Fix it by depending on COMMON_CLK. This only slightly restricts
compilation testing, but not usage of the driver as all platforms on
which the hardware can be found provide COMMON_CLK.

Fixes: 392cd78d

 ("media: bcm2835-unicam: Add support for CCP2/CSI2 camera interface")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202405112243.2MLRT7li-lkp@intel.com/
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>