* tmoddivnode.firstoptimize improvements/fixes:
  * Fixed misplaced parentheses, which were preventing optimization of "unsigned mod power_of_two" into "and" expressions.
  * Handling "signed div power_of_two": properly delete the temp node, removes warnings when compiled with "-dEXTDEBUG". This however requires another temp node for storing the result.
  * Replaced direct calls to "fpc_sarint64" with inline nodes (in_sar_x_y), allowing target-specific optimizations to take place.


git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@25877 3ad0048d-3df7-0310-abae-a5850022a9f2