regulator: fan53555: Remove unused *_SLEW_SHIFT definitions

Commit b61ac767 ("regulator: fan53555: Convert to use
regulator_set_ramp_delay_regmap") removed the slew_shift member from
struct fan53555_device_info, hence the {CTL,TCS}_SLEW_SHIFT definitions
remained unused.  Drop them.
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20230406194158.963352-5-cristian.ciocaltea@collabora.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/fan53555.c

@@ -49,7 +49,6 @@
 /* Control bit definitions */
 #define CTL_OUTPUT_DISCHG	(1 << 7)
 #define CTL_SLEW_MASK		(0x7 << 4)
-#define CTL_SLEW_SHIFT		4
 #define CTL_RESET			(1 << 2)
 #define CTL_MODE_VSEL0_MODE	BIT(0)
 #define CTL_MODE_VSEL1_MODE	BIT(1)
@@ -60,7 +59,6 @@
 #define TCS_VSEL0_MODE		(1 << 7)
 #define TCS_VSEL1_MODE		(1 << 6)
 
-#define TCS_SLEW_SHIFT		3
 #define TCS_SLEW_MASK		GENMASK(4, 3)
 
 enum fan53555_vendor {