x86/intel/quark: Select COMMON_CLK

The commit 8bbc2a13

 ("x86/intel/quark: Add Intel Quark
platform support") introduced a minimal support of Intel Quark
SoC. That allows to use core parts of the SoC. However, the SPI,
I2C, and GPIO drivers can't be selected by kernel configuration
because they depend on COMMON_CLK. The patch adds a COMMON_CLK
selection to the platfrom definition to allow user choose the drivers.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Darren Hart <dvhart@linux.intel.com>
Fixes: 8bbc2a13 ("x86/intel/quark: Add Intel Quark platform support")
Link: http://lkml.kernel.org/r/1425569044-2867-1-git-send-email-andriy.shevchenko@linux.intel.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>