plpsm - plpgpsm: remove return next statement

Log Message:
-----------
remove return next statement
============================
SQL/PSM use table expression

Modified Files:
--------------
plpgpsm/src:
gram.y (r1.55 -> r1.56)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/gram.y.diff?r1=1.55&r2=1.56)
pl_exec.c (r1.58 -> r1.59)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/pl_exec.c.diff?r1=1.58&r2=1.59)
pl_funcs.c (r1.10 -> r1.11)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/pl_funcs.c.diff?r1=1.10&r2=1.11)
plpgpsm.h (r1.44 -> r1.45)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/plpgpsm.h.diff?r1=1.44&r2=1.45)