clk: Use static inline functions instead of macros for dummies

if CONFIG_OF=n:

    drivers/clk/clk-cs2000-cp.c: In function ‘cs2000_remove’:
    drivers/clk/clk-cs2000-cp.c:453:22: warning: unused variable ‘np’ [-Wunused-variable]
      struct device_node *np = dev->of_node;
			  ^

Convert dummies of_clk_del_provider() and of_clk_init() from macros to
static inline functions to kill such compiler warnings.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>