clk: Avoid invalid function names in CLK_OF_DECLARE()

After commit c28cd1f ("clk: Mark a fwnode as initialized when using
CLK_OF_DECLARE() macro"), drivers/clk/mvebu/kirkwood.c fails to build:

 drivers/clk/mvebu/kirkwood.c:358:1: error: expected identifier or '('
 CLK_OF_DECLARE(98dx1135_clk, "marvell,mv98dx1135-core-clock",
 ^
 include/linux/clk-provider.h:1367:21: note: expanded from macro 'CLK_OF_DECLARE'
         static void __init name##_of_clk_init_declare(struct device_node *np) \
                            ^
 <scratch space>:124:1: note: expanded from here
 98dx1135_clk_of_clk_init_declare
 ^
 drivers/clk/mvebu/kirkwood.c:358:1: error: invalid digit 'd' in decimal constant
 include/linux/clk-provider.h:1372:34: note: expanded from macro 'CLK_OF_DECLARE'
         OF_DECLARE_1(clk, name, compat, name##_of_clk_init_declare)
                                         ^
 <scratch space>:125:3: note: expanded from here
 98dx1135_clk_of_clk_init_declare
   ^
 drivers/clk/mvebu/kirkwood.c:358:1: error: invalid digit 'd' in decimal constant
 include/linux/clk-provider.h:1372:34: note: expanded from macro 'CLK_OF_DECLARE'
         OF_DECLARE_1(clk, name, compat, name##_of_clk_init_declare)
                                         ^
 <scratch space>:125:3: note: expanded from here
 98dx1135_clk_of_clk_init_declare
   ^
 drivers/clk/mvebu/kirkwood.c:358:1: error: invalid digit 'd' in decimal constant
 include/linux/clk-provider.h:1372:34: note: expanded from macro 'CLK_OF_DECLARE'
         OF_DECLARE_1(clk, name, compat, name##_of_clk_init_declare)
                                         ^
 <scratch space>:125:3: note: expanded from here
 98dx1135_clk_of_clk_init_declare
   ^

C function names must start with either an alphabetic letter or an
underscore. To avoid generating invalid function names from clock names,
add two underscores to the beginning of the identifier.

Fixes: c28cd1f ("clk: Mark a fwnode as initialized when using CLK_OF_DECLARE() macro")
Suggested-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20230308-clk_of_declare-fix-v1-1-317b741e2532@kernel.org
Reviewed-by: Saravana Kannan <saravanak@google.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: nathanchance

include/linux/clk-provider.h

@@ -1364,12 +1364,12 @@ struct clk_hw_onecell_data {
 };
 
 #define CLK_OF_DECLARE(name, compat, fn) \
-	static void __init name##_of_clk_init_declare(struct device_node *np) \
+	static void __init __##name##_of_clk_init_declare(struct device_node *np) \
 	{								\
 		fn(np);							\
 		fwnode_dev_initialized(of_fwnode_handle(np), true);	\
 	}								\
-	OF_DECLARE_1(clk, name, compat, name##_of_clk_init_declare)
+	OF_DECLARE_1(clk, name, compat, __##name##_of_clk_init_declare)
 
 /*
  * Use this macro when you have a driver that requires two initialization