soc: ep93xx: drop reference to removed EP93XX_SOC_COMMON config

Commit 6eab0ce6 ("soc: Add SoC driver for Cirrus ep93xx") adds the
config EP93XX_SOC referring to the config EP93XX_SOC_COMMON.

Within the same patch series of the commit above, the commit 046322f1
("ARM: ep93xx: DT for the Cirrus ep93xx SoC platforms") then removes the
config EP93XX_SOC_COMMON. With that the reference to this config is
obsolete.

Simplify the expression in the EP93XX_SOC config definition.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Nikita Shubin <nikita.shubin@maquefel.me>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/soc/cirrus/Kconfig

@@ -6,7 +6,7 @@ config EP93XX_SOC
 	bool "Cirrus EP93xx chips SoC"
 	select SOC_BUS
 	select AUXILIARY_BUS
-	default y if !EP93XX_SOC_COMMON
+	default y
 	help
 	  Enable support SoC for Cirrus EP93xx chips.