[patch] Fix execute/va-arg-10.c on h8300 port.

[law@redhat.com]

  In message <200108121508.IAA16809@cygnus.com>you write:
  > Hi,
  > 
  > Attached is a patch to fix the failure of execute/va-arg-10.c on h8300
  > port.
  > 
  > When compiling execute/va-arg-10.c, the original gcc generates an
  > 8-bit displacement jump insn even though the destination cannot be
  > reached within an 8-bit displacement.
  > 
  > This is because the insn length for "zero_extendqihi2" is incorrect.
  > The first assembly insn in the second alternative can be as long as 8
  > bytes, stretching the total up to 10 bytes.  The patch fixes the insn
  > length accordingly.
  > 
  > Tested on h8300 port.  OK to apply to both the branch and mainline?
  > 
  > Thanks,
  > 
  > Kazu Hirata
  > 
  > 2001-08-12  Kazu Hirata  <kazu@hxi.com>
  > 
  > 	* config/h8300/h8300.md (zero_extendqihi2): Correct the insn
  > 	length.
  > 
  > Index: h8300.md
  > ===================================================================
  > RCS file: /cvs/gcc/gcc/gcc/config/h8300/h8300.md,v
  > retrieving revision 1.31
  > diff -u -r1.31 h8300.md
  > --- h8300.md	2001/07/23 21:46:38	1.31
  > +++ h8300.md	2001/08/12 14:55:03
  > @@ -1612,7 +1612,7 @@
  >    "@
  >    mov.b	#0,%t0
  >    mov.b	%R1,%s0\;mov.b	#0,%t0"
  > -  [(set_attr "length" "2,4")
  > +  [(set_attr "length" "2,10")
  >     (set_attr "cc" "clobber,clobber")])
  >  
  >  ;; The compiler can synthesize a 300H variant of this which is