TEST_MATRIX is unaware of local enums

[chrfle]

When using TEST_MATRIX it can't be used with local types.

E.g. I have a enum {A, B}; in my program.c and in my test_program.c I #include "program.c" I can't do:

TEST_MATRIX([A, B], [1,2])

As A and B will be undefined in the testrunner. This forces us to move the enum to program.h. It would be good if local types could be added in the generated testrunner.