(dbxout_parms): For parameters passed in memory, delete
obsolete code to handle parameters converted and stored back to
the stack slot where they were passed in.
(dbxout_reg_parms): Delete obsolete ifdefed out code.  Combine
redundant PARM_PASSED_IN_MEMORY tests.  For case where parameter
lives in memory, output stab if it doesn't live where it was passed.

From-SVN: r9057