linux-imx

arm64: lsdk.config: Remove the definition "CONFIG_DRM is not set"

As per patch "arm64: defconfig: Enables Display support on LS1028A"
, already added option CONFIG_DRM as default. this definition will
override default options set by defconfig.

Otherwise 64-bit ARM builds fail with undefined references to DRM.

Signed-off-by: Wen He <wen.he_1@nxp.com>