clk: Add Ingenic jz4770 CGU driver

Add support for the clocks provided by the CGU in the Ingenic JZ4770
SoC.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18482/Signed-off-by: James Hogan <jhogan@kernel.org>

drivers/clk/ingenic/Makefile

 obj-y				+= cgu.o
 obj-$(CONFIG_MACH_JZ4740)	+= jz4740-cgu.o
+obj-$(CONFIG_MACH_JZ4770)	+= jz4770-cgu.o
 obj-$(CONFIG_MACH_JZ4780)	+= jz4780-cgu.o