pwm: remove unneeded ifdef CONFIG_DM_PWM ... endif

Both CONFIG_PWM_TEGRA and CONFIG_PWM_EXYNOS depend on CONFIG_DM_PWM,
i.e. they are already guarded by Kconfig correctly.  Remove unneeded
ifdef CONFIG_DM_PWM ... endif.

While we are here, let's tidy up alignment and sort the lines
alphabetically in Makefile.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

drivers/pwm/Makefile

@@ -10,10 +10,9 @@
 
 #ccflags-y += -DDEBUG
 
-obj-$(CONFIG_DM_PWM) += pwm-uclass.o
-obj-$(CONFIG_PWM_ROCKCHIP) += rk_pwm.o
-obj-$(CONFIG_PWM_IMX) += pwm-imx.o pwm-imx-util.o
-ifdef CONFIG_DM_PWM
-obj-$(CONFIG_PWM_TEGRA) += tegra_pwm.o
-obj-$(CONFIG_PWM_EXYNOS) += exynos_pwm.o
-endif
+obj-$(CONFIG_DM_PWM)		+= pwm-uclass.o
+
+obj-$(CONFIG_PWM_EXYNOS)	+= exynos_pwm.o
+obj-$(CONFIG_PWM_IMX)		+= pwm-imx.o pwm-imx-util.o
+obj-$(CONFIG_PWM_ROCKCHIP)	+= rk_pwm.o
+obj-$(CONFIG_PWM_TEGRA)		+= tegra_pwm.o