clk: max77686: Combine Maxim max77686 and max77802 driver

clk: max77686: Combine Maxim max77686 and max77802 driver

The clock IP used on the Maxim PMICs max77686 and max77802 are
same. The configuration of clock register is also same except
the number of clocks.

Part of common code utilisation, there is 3 files for these chips
clock driver, one for common and two files for driver registration.

Combine both drivers into single file and move common code into
same common file reduces the 2 files and make max77686 and max77802
clock driver in single fine. This driver does not depends on the
parent driver structure. The regmap handle is acquired through
regmap APIs for the register access.

This combination of driver helps on adding clock driver for different
Maxim PMICs which has similar clock IP like MAX77620 and MAX20024.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
CC: Krzysztof Kozlowski <k.kozlowski@samsung.com>
CC: Javier Martinez Canillas <javier@dowhile0.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>