target_write_memory() function

Write @a count items of @a size bytes to the memory of @a target at the @a address given. @a address must be aligned to @a size in target memory. The endianness is the same in the host and target memory for this function. \todo TODO: Really @a buffer should have been defined as "const void *" and @a buffer should have been aligned to @a size in the host memory. This is not enforced via e.g. assert's today and e.g. the target_write_buffer fn breaks this assumption. This routine is wrapper for target->type->write_memory.