ARM: multi_v7_defconfig: Remove ST_THERMAL_SYSCFG Kconfig symbol

STiH415/6 SoC support is being removed from the kernel and
was the only platform using this Kconfig symbol
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>

arch/arm/configs/multi_v7_defconfig

@@ -450,7 +450,6 @@ CONFIG_RCAR_THERMAL=y
 CONFIG_ARMADA_THERMAL=y
 CONFIG_DAVINCI_WATCHDOG=m
 CONFIG_EXYNOS_THERMAL=m
-CONFIG_ST_THERMAL_SYSCFG=y
 CONFIG_ST_THERMAL_MEMMAP=y
 CONFIG_WATCHDOG=y
 CONFIG_DA9063_WATCHDOG=m