clk: versaclock3: Remove redundant _is_writeable()

The versaclock3 driver provides an _is_writeable() function which returns
true for all registers. This is the default assumption for regmaps so we
can remove the function for a very minor improvement in performance and
code size.

Signed-off-by: Mark Brown <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Stephen Boyd <[email protected]>

Author: broonie

drivers/clk/clk-versaclock3.c

@@ -586,17 +586,11 @@ static const struct clk_ops vc3_clk_mux_ops = {
 	.get_parent = vc3_clk_mux_get_parent,
 };
 
-static bool vc3_regmap_is_writeable(struct device *dev, unsigned int reg)
-{
-	return true;
-}
-
 static const struct regmap_config vc3_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.cache_type = REGCACHE_RBTREE,
 	.max_register = 0x24,
-	.writeable_reg = vc3_regmap_is_writeable,
 };
 
 static struct vc3_hw_data clk_div[5];