kconfig: remove meaningless prefixes in defconfig files

Since commit e02ee2548afe (kconfig: switch to single .config
configuration), the prefixes in defconfig files such as "+S:",
"+ST:", etc., are meaningless.

This commit was generated by the following command:

  find configs -name '*_defconfig' | xargs sed -i 's/^+*S*T*://'

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/configs/Chuwi_V7_CW0825_defconfig b/configs/Chuwi_V7_CW0825_defconfig
index 1ef23e4..03f9361 100644
--- a/configs/Chuwi_V7_CW0825_defconfig
+++ b/configs/Chuwi_V7_CW0825_defconfig
@@ -12,9 +12,9 @@
 CONFIG_VIDEO_LCD_SPI_SCLK="PA1"
 CONFIG_VIDEO_LCD_SPI_MOSI="PA2"
 CONFIG_VIDEO_LCD_PANEL_HITACHI_TX18D42VM=y
-+S:CONFIG_ARM=y
-+S:CONFIG_ARCH_SUNXI=y
-+S:CONFIG_MACH_SUN4I=y
-+S:CONFIG_DRAM_CLK=408
-+S:CONFIG_DRAM_ZQ=123
-+S:CONFIG_DRAM_EMR1=4
+CONFIG_ARM=y
+CONFIG_ARCH_SUNXI=y
+CONFIG_MACH_SUN4I=y
+CONFIG_DRAM_CLK=408
+CONFIG_DRAM_ZQ=123
+CONFIG_DRAM_EMR1=4