ARM: imx: move clock drivers into drivers/clk

After the cleanup on clock drivers, they are now ready to be moved into
drivers/clk.  Let's move them into drivers/clk/imx folder.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 3d00c25..d7a507f 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -50,6 +50,7 @@
 obj-$(CONFIG_ARCH_HI3xxx)		+= hisilicon/
 obj-$(CONFIG_ARCH_HIP04)		+= hisilicon/
 obj-$(CONFIG_ARCH_HIX5HD2)		+= hisilicon/
+obj-$(CONFIG_ARCH_MXC)			+= imx/
 obj-$(CONFIG_COMMON_CLK_KEYSTONE)	+= keystone/
 ifeq ($(CONFIG_COMMON_CLK), y)
 obj-$(CONFIG_ARCH_MMP)			+= mmp/