lib/glob: convert selftest to KUnit

This patch converts the existing glob selftest (lib/globtest.c) to use the
KUnit framework (lib/tests/glob_kunit.c).

The new test:

- Migrates all 64 test cases from the original test to the KUnit suite.
- Removes the custom 'verbose' module parameter as KUnit handles logging.
- Updates Kconfig.debug and Makefile to support the new KUnit test.
- Updates Kconfig and Makefile to remove the original selftest.
- Updates GLOB_SELFTEST to GLOB_KUNIT_TEST for arch/m68k/configs.

This commit is verified by `./tools/testing/kunit/kunit.py run'
with the .kunit/.kunitconfig:

CONFIG_KUNIT=y
CONFIG_GLOB_KUNIT_TEST=y

Link: https://lkml.kernel.org/r/20260108120753.27339-1-note351@hotmail.com
Signed-off-by: Kir Chou <note351@hotmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Cc: <kirchou@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/m68k/configs/bvme6000_defconfig

@@ -549,7 +549,6 @@ CONFIG_CRYPTO_USER_API_AEAD=m
 CONFIG_PRIME_NUMBERS=m
 CONFIG_CRC_BENCHMARK=y
 CONFIG_XZ_DEC_TEST=m
-CONFIG_GLOB_SELFTEST=m
 # CONFIG_SECTION_MISMATCH_WARN_ONLY is not set
 CONFIG_MAGIC_SYSRQ=y
 CONFIG_TEST_LOCKUP=m