Set PATH_EXT for djgpp

[Mark E.]

Hello,
This patch sets PATH_EXT for djgpp since it too uses ".exe" as an 
executable suffix.

*** aclocal.m4.orig     Sat Aug 11 22:09:14 2001
--- aclocal.m4  Sun Aug 12 18:07:08 2001
*************** os2*)
*** 1905,1911 ****
      LDFLAGS=`echo "$LDFLAGS -Zmt -Zcrtdll" | sed "s/-Zexe//g"`
      PROG_EXT=".exe"
      ;;
! cygwin*)
      PROG_EXT=".exe"
      ;;
  esac
--- 1905,1911 ----
      LDFLAGS=`echo "$LDFLAGS -Zmt -Zcrtdll" | sed "s/-Zexe//g"`
      PROG_EXT=".exe"
      ;;
! cygwin* | msdosdjgpp*)
      PROG_EXT=".exe"
      ;;
  esac