tests: lib: smf: Add missing equals

When building with clang and -Wno-gnu it complains about the missing
equals:

tests/lib/smf/src/test_lib_hierarchical_5_ancestor_smf.c:415:8: error:
use of GNU 'missing =' extension in designator
[-Werror,-Wgnu-designator]

[P05] SMF_CREATE_STATE(p05_entry, p05_run, p05_exit, NULL, NULL),
      ^
      =

tests/lib/smf/src/test_lib_hierarchical_5_ancestor_smf.c:416:8: error:
use of GNU 'missing =' extension in designator
[-Werror,-Wgnu-designator]

[P04] SMF_CREATE_STATE(p04_entry, p04_run, p04_exit, &test_states[P05],
      ^                NULL),
      =

tests/lib/smf/src/test_lib_hierarchical_5_ancestor_smf.c:417:8: error:
use of GNU 'missing =' extension in designator
[-Werror,-Wgnu-designator]

[P03] SMF_CREATE_STATE(p03_entry, p03_run, p03_exit, &test_states[P04],
      ^                NULL),
      =

tests/lib/smf/src/test_lib_hierarchical_5_ancestor_smf.c:418:8: error:
use of GNU 'missing =' extension in designator
[-Werror,-Wgnu-designator]

[P02] SMF_CREATE_STATE(p02_entry, p02_run, p02_exit, &test_states[P03],
      ^                NULL),
      =

tests/lib/smf/src/test_lib_hierarchical_5_ancestor_smf.c:419:8: error:
use of GNU 'missing =' extension in designator
[-Werror,-Wgnu-designator]

[P01] SMF_CREATE_STATE(p01_entry, p01_run, p01_exit, &test_states[P02],
      ^                NULL),
      =

Signed-off-by: Tom Hughes <tomhughes@chromium.org>