regmap: Cache register and value sizes for debugfs

No point in calculating them every time.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/base/regmap/internal.h

@@ -50,6 +50,10 @@ struct regmap {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs;
 	const char *debugfs_name;
+
+	unsigned int debugfs_reg_len;
+	unsigned int debugfs_val_len;
+	unsigned int debugfs_tot_len;
 #endif
 
 	unsigned int max_register;