* MIPS: fixed layout of stack frame in case procedure does only low-level calls (via a_call_name, etc.). A 16-byte outgoing parameter area must be allocated regardless of actual parameter count.
* Abort if attempting to emit a call without pi_do_call flag set, because the outgoing parameter area determines layout of temps and therefore cannot be created/changed during pass 2.
* Bypass g_concatcopy_move if procedure is a leaf one, due to the restriction mentioned above.

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@23644 3ad0048d-3df7-0310-abae-a5850022a9f2