tests: userspace: Incorrect location to the privileged stack.
tests: userspace: Incorrect location to the privileged stack.

The test case was supposed to access the privileged stack area
but instead it was accessing the stack guard region.

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

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