ARM: Remove deprecated symbol from defconfig files

Commit b2b3a8b9 ("power/reset: Remove sun6i reboot driver") removed
the sun6i reboot driver. But sunxi_defconfig and multi_v7_defconfig
still contain the symbol CONFIG_POWER_RESET_SUN6I that was deprecated
by that commit, so remove it.
Signed-off-by: Timo Sigurdsson <public_timo.s@silentcreek.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/configs/multi_v7_defconfig

@@ -319,7 +319,6 @@ CONFIG_POWER_RESET_AS3722=y
 CONFIG_POWER_RESET_GPIO=y
 CONFIG_POWER_RESET_GPIO_RESTART=y
 CONFIG_POWER_RESET_KEYSTONE=y
-CONFIG_POWER_RESET_SUN6I=y
 CONFIG_POWER_RESET_RMOBILE=y
 CONFIG_SENSORS_LM90=y
 CONFIG_SENSORS_LM95245=y

arch/arm/configs/sunxi_defconfig

@@ -77,7 +77,6 @@ CONFIG_SPI_SUN6I=y
 CONFIG_GPIO_SYSFS=y
 CONFIG_POWER_SUPPLY=y
 CONFIG_POWER_RESET=y
-CONFIG_POWER_RESET_SUN6I=y
 CONFIG_THERMAL=y
 CONFIG_CPU_THERMAL=y
 CONFIG_WATCHDOG=y