benchmarks: footprint: Disable userspace for benchmarks
benchmarks: footprint: Disable userspace for benchmarks

Disable userspace for benchmarks because it changes the KPI
numbers. It will be re-enabled once the required code is
in place.

Signed-off-by: Adithya Baglody <06b44f6fa9a97a2b955c2d2cd070279967447860@intel.com>

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