Input: synaptics-rmi4 - use Kconfig "if" to express dependency

There is no need to repeat "depends on RMI4_CORE" on every bit of RMI4
support, we can guard all of them at once with "if RMI4_CORE".

Also use tabs for F03 indentation.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>