* spu/jsre.h: Remove the assist call structs and defines that are
specific to one assist call from here.
* spu/access.c: Move struct syscall_access_t to here.
* spu/fstat.c: Move struct syscall_fstat_t to here.
* spu/ftruncate.c: Move struct syscall_ftruncate_t to here.
* spu/gettimeofday.c: Move struct syscall_gettimeofday_t to here.
* spu/lseek.c: Move struct syscall_lseek_t and JSRE_SEEK defines to
here.
* spu/open.c: Move struct syscall_open_t and JSRE_O_ defines to here.
* spu/read.c: Move struct syscall_read_t to here, and actually use
it (it is the same as syscall_write_t).
* spu/stat.c: Move struct syscall_stat_t to here.
* spu/write.c: Move struct syscall_write_t to here.
* spu/close.c: Pass the address of the first and only argument to
__send_to_ppe rather than using an automatic variable and a
special struct.
* spu/dup.c: Ditto.
* spu/unlink.c: Ditto.