[PATCH 3/5] Documentation: update the of_selftest.txt

Since the directory "drivers/of/testcase-data" is renamed to "drivers/of/unittest-data". so we should update the path in the of_selftest.txt. When the kernel is built with OF_UNITTEST enabled, the output dtb is testcases.dtb instead of testcase.dtb, also update it (s/testcase/testcases/).

[PATCH 3/5] Documentation: update the of_selftest.txt

Since the directory drivers/of/testcase-data is renamed to drivers/of/unittest-data. so we should update the path in the of_selftest.txt. When the kernel is built with OF_UNITTEST enabled, the output dtb is testcases.dtb instead of testcase.dtb, also update it (s/testcase/testcases/).