pkg/ubuntu: config: Remove CONFIG_INTEL_IOMMU_DEFAULT_ON=n

The option was originally set to 'n' to prevent IPTS from breaking. We
now have patches that fix that in a more direct way, so we can drop this
workaround.

pkg/debian/kernel/ubuntu.config

@@ -62,12 +62,6 @@ CONFIG_ACPI_I2C_OPREGION=y
 
 # CONFIG_INPUT_EVBUG is not set
 
-##
-## Do not enable Intel IOMMU by default, it breaks IPTS/ME.
-##
-
-CONFIG_INTEL_IOMMU_DEFAULT_ON=n
-
 ##
 ## Config options required for backlight on Surface 3.
 ##