sparc: Add module.h to files previously implicitly using it.

The file mm/extable.c needs module.h for within_module_init(), and
also for search_exception_tables [which arguably could be living somewhere
more appropriate than module.h] - eventually causing this:

arch/sparc/mm/extable.c: In function 'trim_init_extable':
arch/sparc/mm/extable.c:74: error: dereferencing pointer to incomplete type
arch/sparc/mm/extable.c:75: error: dereferencing pointer to incomplete type
arch/sparc/mm/extable.c:77: error: implicit declaration of function 'within_module_init'
arch/sparc/mm/extable.c:77: error: dereferencing pointer to incomplete type
arch/sparc/mm/extable.c:78: error: dereferencing pointer to incomplete type
arch/sparc/mm/extable.c:80: error: dereferencing pointer to incomplete type
arch/sparc/mm/extable.c: In function 'search_extables_range':
arch/sparc/mm/extable.c:93: error: implicit declaration of function 'search_exception_tables'

The other instances are more straight forward uses of things
like MODULE_* and module_*

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>