imx: mx8m: add clock driver

Add clock driver to support i.MX8M.

There are two kind PLLs, FRAC pll and SSCG pll. ROM already
configured SYS PLL1/2, we only need to configure the output.
ocotp/i2c/pll decoding and configuration/usdhc/lcdif/dram pll/
enet clock are configured in the code.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/mach-imx/mx8m/Makefile b/arch/arm/mach-imx/mx8m/Makefile
new file mode 100644
index 0000000..05f3884
--- /dev/null
+++ b/arch/arm/mach-imx/mx8m/Makefile
@@ -0,0 +1,7 @@
+#
+# Copyright 2017 NXP
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += clock.o clock_slice.o