selftests/mm: fix spelling

Fix misspelling flagged by codespell.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ujwal Kundur <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

tools/testing/selftests/mm/uffd-common.c

···
 	/*
 	 * After initialization of area_src, we must explicitly release pages
 	 * for area_dst to make sure it's fully empty.  Otherwise we could have
-	 * some area_dst pages be errornously initialized with zero pages,
+	 * some area_dst pages be erroneously initialized with zero pages,
 	 * hence we could hit memory corruption later in the test.
 	 *
 	 * One example is when THP is globally enabled, above allocate_area()