x86: disable CONFIG_EFI_VARS

Disable CONFIG_EFI_VARS, since it suffers from sysfs limitation (no
support for variable longer than 1024 bytes).

kmod-fs-efivarfs is the replacement of this, which enables mounting
efivarfs file system and doesn't suffer from 1024 bytes limitation.

Signed-off-by: Alif M. Ahmad <alive4ever@live.com>

target/linux/x86/64/config-default

@@ -113,7 +113,7 @@ CONFIG_EFI_RUNTIME_MAP=y
 CONFIG_EFI_RUNTIME_WRAPPERS=y
 CONFIG_EFI_STUB=y
 # CONFIG_EFI_TEST is not set
-CONFIG_EFI_VARS=y
+# CONFIG_EFI_VARS is not set
 CONFIG_FB=y
 CONFIG_FB_CFB_COPYAREA=y
 CONFIG_FB_CFB_FILLRECT=y